If the bot problem is bad enough, it will most likely be welcomed. Anyway, shouldn’t be much of an issue with a reasonable threshold that 95% of legitimate players would unlikely trigger.

If captches would be easy to beat you would have tons of spam on forums or image boards, yet there is practically zero.

There are also a lot easier captchas that are even faster to slove and impossible for bots e.g. picture captchas where you have to arrange puzzel pieces or select the cats from a dog pool.
Which all can be done in less then 10 seconds. Hell this would be prefect for WoT where you can combine it with the Tanks ingame.

Not to mention most “I bet tha captcha” remarks come from actually circumventing it and not beating it. Aka make use of sloppy made webpages.

WoT CN has so many bots that hardly anyone bothers to report them. If you report every bot on your team you’ll use up your chance to report in two battles.