I'm also interested in DAOs and sidechains, but am a layman, my technical knowledge is pretty shallow.

If OP_CTV and Anyprevout are implemented, which I think are the requirements for something like a spacechain, and later we do what Russell O'Connor was saying here: https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-January/019813.html and implement TXHASH + CSFSV as a more generalized approach. Could those sidechains be moved to the new code relatively easily?

I ask because while I agree with you that we shouldn't wait two years to wait two more years to wait two more years to do the perfect thing. But, I don't have the technical knowledge to pontificate on a theoretical sidechain migration.

(side note: I wrote a randomly really long post about error correction and innovation in Bitcoin on the UnHashed podcast telegram group about this, lol--The topic comes up on their most recent podcast (ep 147 like 30 minutes in)---this post here is a much simpler/casual version of that).