The idea is old, true, the implementation is different. Instead of replacing the arbitrage of centralized donation processors with crypto and miners (like in the systems you mention), we rather go without middlemen.

We focus on privacy - I wouldn’t want my micro-donations to political parties and porn sites to go through a central processor or crypto exchange (with KYC) and be eventually leaked.

Spam won’t be an issue for systems requiring registration like Lemmy or for direct end-to-end donations. Yet, you are right, we had to develop anti-spam/fake measures for the general case where users are anonymous and smartlikes are accumulated in charts to boost channel visibility and help users discover new content. These are crowdsourced decentralized moderation - https://blog.smartlike.org/censorship-and-moderation - and an optional type of donation where a % is cut and evenly distributed among all creators…