7D2D isn't a survival game in the first place.
It's a looter-shooter that has also some - rather basic - survival aspects to it.
People who would rather like to see its survival aspect being more predominant are disappointed by the water changes,
because they see the "real life survival logic" being cut from the game.
Especially in an "urban postapocalyptic suvival situation" - which obviously is exactly the theme of 7D2D - there should be an overabundance of empty ( or reusable full) containers which could be found all over the place, and you'd have no problem to get these (emtpy bottles and alike) and use them to collect water, fuel, and whatever other fluids you want and take it with you.
That obvious break of logic is what bugs people.
They're not really complaining that the game doesn't work anymore, in fact many people say that water is still too easy to get. It doesn't matter.
So yes, the decision that TFP decided to get rid of emtpy containers does work gameplay wise, but with said downside.
Making water scarce is...questionable and may still be subject to further balancing.
But really there is no need to try and explain these people from end to end why their opinion that there should be empty containers in the game is (allegedly) bad/wrong/logic breaking/...
When somebody says he wants to fetch water from a lake and doesn't like that this is gone,
just tell him: YES! In that aspect, that decision totally sucks! Basic survival logic was taken away from a game that claims to (also) be a survival game.
But it was for the good of other aspects that profit from that desicion. And yes it works smooth overall, despite the "stupidity" that...and many other things too if you think carefully.
This is not The Long Dark...and I'm glad it isn't.
...well, considering the length this post has reached...the long dark might apply somehow to it...sorry...