The internet is no longer a safe haven

I wonder if a proof of work protocol is a viable solution. To GET the page, you have to spend enough electricity to solve a puzzle. The question is whether the threshold could be low enough for typical people on their phones to access the site easily, but high enough that mass scraping is significantly reduced.

There's this paper from 2004: "Proof-of-Work Proves Not to Work": https://www.cl.cam.ac.uk/~rnc1/proofwork.pdf

The conclusion back then was that it's impossible to make a threshold that is both low enough and high enough.

You need some other mechanism that can distinguish bad traffic from good (even if imperfectly), and then adjust the threshold based on it. See, for instance, "Proof of Work can Work": https://sites.cs.ucsb.edu/~rich/class/cs293b-cloud/papers/lu...