- `feed.star` and `feed.subscription` still have to use TID. - DID itself doesn't enforce the uniqueness because it's case-insensitive - we can't enforce DID rkey from lexicon schema. We can't benefit from existing atproto sdks for that and we will have to check that in runtime. So using DID in rkey earns nothing. We should handle duplications anyway, and that will be more problemetic when we add more fields in `follow` record. It's not that hard to imagine supporting follow-for-events feature in future. We know this problem exists, so we should avoid using DID as rkey at first place. Either way, indexers like Bobbin have to deal with duplication anyway, so we don't really loose anything here. Signed-off-by: Seongmin Lee <git@boltless.me>