There are no bad countries, only bad streams of traffic.

Some of which have been observed to be associated with certain countries.

I believe even a cursory examination of recent history to show your premise to be less than truthful.

There are bad actors. There are bad groups of actors. There are bad political regimes of groups of bad actors. There are countries made up of bad political regimes made up of groups of bad actors.

If you spend any time at all at a cloud hosting provider, you'll quickly learn there are only a few bad countries. It's not really Russia IME, it is mostly India and China. If you block those two, you're going to eliminate 99% of your abuse.

I'm curious, what's the method you chose to block them? Do you use some IP list provided from some geolocation service?