I’ve found on my small site that I get about 5 spam signups a day, and maybe a spam posting once every 2-3 days. Not from Russia - from India and (I think) Vietnam. Usually I am able to catch them pretty fast and as long as I keep up with it the task doesn’t get too onerous.
And because the spam users are barely visible to the outside world, their impact is neglible.
I love this! I was not aware of this but just tried it out and it really helps. Thanks!