> Anyway, I would’ve thought it’s an acceptable cost from e.g. Google’s perspective to block ranges that did something bad once in spite of collateral damage.

Almost nobody is on a static IP. ISPs have an interest to keep their customers connected and not affected by other customers, so they'd probably use as large address pools as possible for their dynamic IP rotations. "Did something bad once" is short-lived unless address ranges are large.

Tech companies like Google are interested in being global monopolies to dominate markets and also having as good and large-sampled statistical data as possible from everyone. Blocking thousands of users for each bad user that can likely easily switch to another block if they really want to doesn't seem effective. It would also affect their reputation. Who wants to rely on an email service that may block you because of other users on your IP block? Having a reputation for being reliable is important for businesses.

With small personal sites/blogs like the ones you mentioned, they can just block most of the planet without a problem. There's not as much reason to be as reachable as possible (some may be satisfied with an audience of a handful of people), and they're also more budget conscious.

In the case of Google blocking an Apple service, they not blocking users; they're blocking Apple. The users can just not use Apple's service.