As someone currently using a swamp cooler in a desert climate with daily temps around 40C, that statement is absolutely misleading!
A more accurate statement could be that they cycle 125-550L of water a day, but aside from what's evaporated, it's basically a closed-loop system, with very little water waste or loss.
evaporative coolers are very common in desert climates in the US. they work really great up to about 60% humidity and cost less than 10% to operate compared to 'regular' AC. they use little power (can easily be solar powered), and do not pollute.
i have both an evaporative cooler and an AC unit and have rarely felt the need to use the AC - the evap works exceedingly well for keeping the temps tolerable.
the only real downside is that it's not just push a button and all your problems are solved. you need airflow. usually these things are mounted where the output vents into a central hallway or room, and you direct the flow of cool air by opening windows or doors - the path between the cooler vent and the open "exhaust" to the outside is what stays the coolest. Opening the whole house requires turning the evap cooler's fan to a higher speed, but that's so wasteful and we're not ever using the whole house at once. i also turn it off when there's a thunderstorm (because obviously the humidity spike makes this useless). It also doesn't get used in the winter - it gets a canvas cover and some padding to seal off the air gaps so the house doesn't get too cold and drafty.
it's clear there's a lot of people here who haven't ever used or even seen this type of cooler, but i assure you this is common, and probably the most cost-effective summer cooling.
pretty sure the venn diagram of f-droid users and adblocking users is such a huge overlap that this may not pay off too well.