Farcaster

honest confession: i never learned what parts of fc are onchain and at this pt im too afraid to ask

does it matter? should it matter?  Maybe, but not if it's only needed to artificially differ from e.g. bluesky. There is some blockchain used....

it probably matters if u want ppl building stuff on top of the protocol or u want to tightly couple other things that smart contracts are good at, no?

Yes, but what was encouraged and done was other clients. I tested only one of them, but obviously inferior apart 1 additional feature and it aimed for monetization of this feature ofc. Hard to compete with a free client of the OG vendor then. And the extensions like frames weren't open. With frames v1 discontinue an example is already made that what was build by others can be quickly broken. Big "web2" companies do this often, but then what is permissionless with farvaster  or decentral? That's why blockchain doesn't matter for it as-is. Which doesn't mean that warpcast is bad, only i struggle to see a real difference.