[sshumaker]

This would be easily exploitable by a competitor. For example, search engines (used to) rank back links - that is other domains pointing to your domain. Some bad actors took advantage of this by creating rings of sites that voted each other up. Google responded by punishing the behavior. Then, competitors started taking advantage of this punishment by creating a network of sites that backlinked to a competitor, so they would get punished instead.

This isn’t a hypothetical example - Google actually includes in their webmaster tools a “disavow links” capability so sites can avoid getting punished for bad actors trying to make them look bad. But you can imagine if the penalties were even more severe other folks may get caught up in an unforgiving dragnet with no judge or jury and no way to appeal.

My main point is that people will find ways to game the system, and usually sharp edges (“harsh punishments”) on any system will be taken advantage of by actors, and unfairly penalize others.

[Nextgrid]

Agreed, I'm not saying this is the end-game or that it will be perfect. But a simple rule (that's actually enforced) saying that you are forbidden to serve a different experience to the Google bot vs a normal visitor would take care of Pinterest for example, and they're not even doing that despite it being a major complaint especially in tech-circles where Googlers no doubt lurk.