Seems like a serious issue many sites have nowadays. I really don't want this solved by Captchas everywhere.

If it comes to it, just block all known IP blocks of cloud providers.

There are likely a number of beneficial bots[0] running from cloud providers. And residential proxies are also widely available for very determined scrapers.

[0]: <https://stuartgeiger.com/talks/2013-08-03-wikisym-levee-brea...>