Comment by charcircuit

>By what measure?

Time and money lost to them. The idea of creating a web closed from those people starts to look very attractive when you have to spend time multiple times a day cleaning out spam from your site.

>Under what conditions you think spam/fraud would (more or less) 'destroy' the open web?

It's already happening.

>And what does that destruction look like to you?

The destruction looks like more websites able to offer free or cheap services. A great reduction in spam comments. More effective ads. For good actors nothing really changes.