The second-largest cryptocurrency is about a year away from a sharding system that multiplies scale by a factor of 512, with room to grow as hardware improves.

The second-largest cryptocurrency is about a year away from a sharding system that multiplies scale by a factor of 512, with room to grow as hardware improves. That's for purely on-chain transactions. There's also a partly-offchain solution called "zkrollups" that uses zero-knowledge proofs to reduce the storage for a simple value transfer to 11 bytes, without introducing any unpleasant security assumptions like requiring the user to be online to receive payment or prevent cheating. Combining that with sharding gets to about a quarter million tx/sec. If that's not sufficient for micropayments, it's fairly straightforward to extend zkrollups to make payments probabilistic: e.g. to pay one penny, send a 1% chance of paying a dollar. There are some potential doublespending issues here but for voluntary tips that's not a problem.