certainly for me now, i can easily create between 1 to 3 dew collectors very early on; i forget what is needed to be able to get the ability to craft them. but once you can, i am able to as i mass-collect polymers from everywhere, not just tyres on the ground but the squished plastic on the ground too, they're extremely plentiful; - i don't recall seeing any of the main youtube content creators every harvest the squished plastic so maybe it's not a well-known thing
p.s. i rarely bother with the 3 mods that you install in the new dew collectors, to me there's just no point, murky water for me is fine, i just boil any on a campfire as soon as i have any. plus a great trick i now employ is to put a campfire on a storage box when out raiding, so i can boil any murkies out-and-about, if i'm far from home and lacking drinkable water/tea's