A few thoughts based on a number of different posts above...
If you only loot one POI per day, you're possibly going to struggle with water. If you loot a few a day or even every couple of days, water shouldn't be an issue for drinking. If you maintain this pattern, by the time you are cooking food that needs water, you shouldn't have any issue with water to do so. This is all without any dew collectors in at least 1-2 player games. For larger groups, this may vary depending how many are looting and how many places are looted in a day. Obviously, if larger groups aren't looting enough POI to get enough murky water to boil for the entire group, then you are going to need dew collectors to compensate. So this creates a very different game experience based on the number of players, which I don't think is a good thing. If a solo player can easily ignore dew collectors without even putting in any effort (if they are looting regularly) and a group of 8 has almost no choice but to have a dew collector farm just to manage thirst, with other numbers of players falling between those extremes, that's not a good balance, imo.
In a solo or 2 player game, I have not had any difficulty with water. Yes, I do quest often but questing doesn't get me water any more than if I'm just looting. I don't buy drinks from the trader. I don't need to buy a bunch of filters since I don't need dew collectors, so quests don't help me there either. I've yet to need to buy a pot because I find them everywhere. For anyone who is struggling, they have the option if they need to of getting 10 water from tier 1 quest rewards probably about once in every 3 quests, give or take. If you quest once per day and you need water and can't seem to get enough murky water, this is enough to keep you going all on its own. Murky water is everywhere. I can come out of most tier 1 POI with a minimum of 5 murky water and often more. That's enough for a couple of days for a person. So if you are looting only 1 POI per day, you should still have plenty for drinking. If you loot more than that, you'll start stockpiling it really quickly and have plenty once you're ready to start cooking food that needs water. Of course, you can also just stick to cooking food that doesn't need water. I hate constantly eating such lower food but it's an option for those who don't mind it and there's no need for water and plenty of meat to make that possible. And this is all with even drinking plain boiled water instead of making teas or other drinks that are a far more efficient use of the murky water.
What this comes down to is that water is not scarce in the first couple of days if you have even the slightest interest in looting. If you want to avoid all looting, then sure... it's an issue. But if you loot even one or two a day, there's no reason you shouldn't have plenty of water immediately. Day 1, you're covered by the 2 water you start with. By day 2, you should have found some murky water without any effort and so it isn't an issue. You should be already starting to get enough murky water by day 3 to start stockpiling it (albeit in small numbers initially). So I really don't consider the change to be at all a challenge in the first days or at all scarce.
Now... Roland has been stating that water is meant to be scarce in the first couple of days to a week (if you are having trouble in a week and aren't in a large group of players who don't want to loot much, there's a problem) and that there isn't an intent for it to be an issue long term. As I've said above, it isn't an issue in the beginning if you put even the absolutely bare minimum of effort in to loot a POI once a day. As for long term, the fact that they bumped duct tape requirements up so high in recipes means that you are actually making it more of a challenge in mid- to late-game for anyone who wants to do a lot of crafting. So it actually seems to be the opposite of the stated intent. Not any more difficult in the first few days (you may need to adjust how you play a bit if you never looted before) and instead a requirement to spend time setting up a large dew collector farm if you want to do any serious crafting in the later game.
Now, I will point out that I gave up crafting in A21 except for tier 1 weapons and specific things like vehicles, gas, ammo, building blocks, etc. I don't see any reason to make thousands of duct tape just to craft stuff. I'd rather just find it, even if it can take longer to do so. It isn't that I can't make the duct tape. I just don't feel like bothering with it. If the recipes were the same as in A20, I'd be crafting all kinds of stuff but, oh well. So, yes, I don't need water for much beyond cooking and drinking. But we're really talking about early game and you don't need much duct tape until you're past the point where you're "supposed to" be no longer struggling with water, right? So it doesn't really change anything. I've yet to have any difficulty with water. There may have been times when I didn't have anything to drink because I forgot to boil water and so I starting boiling the stack of 20+ murky water sitting in my inventory and it took a few minutes of waiting so I could drink something, but that isn't an actual challenge.
Yes, I do loot a lot. In the early game, I like going through the various POI and finding stuff. That gives me a ton of murky water. Others don't do this and I get that. But as I mentioned, one POI a day should easily give you enough murky water to last you at least a day, especially if made into tea. If you did 3 on your first day (no quest required), you could have enough water to last you a week without having to loot again during that week (this is per person, to be clear). I just don't see in any game I've done in A21 even the slightest difficulty with water. Yes, I'm not in an 8 player game where some won't leave the base, but as I said earlier, that just emphasizes that the balance is off enough to make small groups have no problem and large groups have problems, which I still say isn't a good thing. And even then, I would think you'd have one or two people in the group who enjoy looting and can loot 4 or 5 tier 1s in a day between them, which should easily cover drinking and cooking water for the group even if no one else in the group helped.
And to be clear, this is on default loot settings. If you reduce the loot abundance, you could have more difficulty. Other difficulty settings may also make it more challenging. However, as this is a choice to change these settings specifically to increase difficulty, I don't think that's a problem.