Thousands of brute force login attempts per day gone. The effect is, as you say, small, but it was non 0 and now it is 0, and it's a bunch of noise I don't have to wade through.
> Failed login attempts / brute force attempts seem like the cost of doing business in public.
Yup, and I pay that cost by blocking the source of 98% of them.
> purely like a fear response with no rational basis (or at least a poor understanding of probability / stats)
Thanks, clearly you know me well /s. And honestly, again, I don't feel that I even NEED a rational basis. It's my system, I'll block whomever I feel like blocking for whatever reason I want, thanks. If you want to deride me by calling into question my motives, you can do that too for whatever reason YOU want to, but that's on you.
You are free to act under whatever impetus you want and while I did call in to question your motives (implicitly), I never meant that as a derision. I frequently ask myself "why am I doing this?". It usually doesn't hurt to self reflect.
Edit: Something about this kept nagging me. And I think its this:
>It's my system, I'll block whomever I feel like blocking for whatever reason I want, thanks.
I see parallels to a sentiment that used to be fairly common in the U.S.:
"It's my store, I'll refuse whomever I feel like refusing for whatever reason I want, thanks"
Laws against that kind of thing are relatively new (1964?). You have a valid reason to block certain users (hacks) but do you really not see a problem extending that to national origin?
As you mentioned, simply ban couldn't help less. But anyway, their servers, their choices. I've no comment on that.
Failed login attempts / brute force attempts seem like the cost of doing business in public. I assume that if my servers are accessible from 1 or more public addresses, they WILL be subject to brute force attempts. I also assume that by making my passwords sufficiently randomized, the probability of these attacks having any effect is infinitesimal.
To me, blocking an IP because it tried to log in to your servers seems purely like a fear response with no rational basis (or at least a poor understanding of probability / stats). By extension, blocking a range of IPs because of some arbitrarily elevated frequency of login attempts seems equally silly.
Now for DOS attacks, temporary IP blocks make perfect sense.