Although these bots surely ruined their income, there's also other factors to why they were banned (for sure). Some do tend to abuse a bit by posting more ads on their respective pages than the limit imposed by adsense, some do use two adsense accounts so they could use more of their ads on a single page (an issue that has started since a month ago that these faucets had their accounts banned by adsense too). Sadly the fix to these types of problem (bots), it's easier said, than done since for some reason, no matter how many types they alter the codes for securing the faucet against bots, the programmers always find a way to bypass it and it seems anything automated would have the same effect unless everything is check and done completely manually (in which no one has the time to do it).
i agree that bots were not the sole reason all faucets have had their adsense accounts disabled or banned.
also i agree that some programmer will continue to find a way to by pass the protection. No matter how much money you have or even what government you are, there has been someone that has broken their security. Computers are only as good as we program them to be. Just like everything else where technology has evolved and has been upgraded, anti bot measures will need to be updated as needed.
one measure i just found i believe is a temporary fix now that will add a small yearly expense to each faucet but then again its better then having their ad marketing companies pulling their ads all together giving you zero income.
the one measure i found so far is Botdetect which can be viewed and even demoed at
https://captcha.com/even with this software fix i believe that some parts of Botdetect program already has been broken by different and various sources and some of the program is already on bot forums to be requested to crack it.