If the ISPs do their job and handle abuse emails, less people would be blocking IP ranges like this.

There's a reason in IP abuse or spam databases, certain countries light up like a christmas tree and others are not used for these purposes. If you do nothing to be a good citizen of the Internet, all the bad citizens are attracted to you as an ISP.

You shouldn't even need to email the ISP for abuse, they should just detect it themselves. But even taking actions on the emails seems too difficult for them, so I doubt we'll see anything pro-active.

My guess is that India has been blocked so that the website owner is able to join a particular ad network (in this case Mediavine) which pays well but requires primarily US traffic. So it’s easier to just block the visitors that are preventing you from joining. Ruthless but commercial decision.

... and yet most of the spam is originated from US IP addresses.

Checking the revenue analytics for my blog.

US visitors made up 66.13% of my revenue, with 14% of spam coming from US IPs.

India made up 0.14% of my revenue, with 5% of spam coming from Indian IPs.

Russia made up 0% of my revenue, with 21% of spam coming from Russian IPs.

I don't do geo-blocking on my website since my spam filter catches pretty much everything these bots are spewing out, but I can certainly see why someone might want to do it. Especially if they're wasting time/money dealing with spam or automated attacks.

How does geoblocking a website help with spam email?

What kind of abuse threats does a static site showing a bunch of ad-ridden articles get that isn't already covered in basic Cloudflare filtering?