This has been used by record labels in the past. I can't remember which system tried to do reputation (was it kazaa?), but some of the most upvoted songs were the current hits, but replaced with a ~10s loop going for a few minutes.

Now, do you think you can outvote riaa enforcement group equivalent, if they decide so spend money on this?

Bitcoin originally evolved from the "hashcash" proof-of-work system, which was intended to be a scalable anti-spam measure (force an attacker to generate a unique proof that is expensive to generate but cheap to verify). And you are basically describing proof-of-stake (force participants to stake, and if they misbehave you slash their stake). I wasn't kidding about "nothing is new under the sun" ;)

In general though others are right that the problem often is that attackers are more willing to play these games than individuals - you are not willing to put up 10 bucks to post on a web forum, but an attacker might think $10 to get a wonderful commercial offer delivered to 1000 people sounds really good! You won't spend 10c to upvote each individual song, but the RIAA will! Etc. It needs to be highly asymmetrical, and ideally have minimal/zero cost to "honest" users with an exponential penalty for attackers.

Obviously we are not living in a post-email-spam world unfortunately, and what we have is basically the "lightning network" with gatekeepers offloading and centralizing a lot of the problem so users don't have to deal with it. But you aren't the first person to make the observation that these are related problems!

> Its going to be an unpopular take, but crypto solves this. As in currency. Make people attest to things with locking a very small amount of money.

So claims Elon on Twitter, a platform that is very obviously to anyone who uses it completely overrun with bots who have found it very profitable to validate their spam accounts and get preferential listings for a mere eight dollars, while scaring off legitimate users who (fairly) do not trust a service with no functioning security department with their payment information.