semisol on Nostr: I would say that the figure of 1000 notes for a feed is too much. It is usually ...

I would say that the figure of 1000 notes for a feed is too much. It is usually enough to fetch 100-200.

Even in this case, advanced relays like Nostr.land already apply compression to the sent data.

The codepath duplication caused by kind 1 is limited. It would be treated like a reply either way, with slightly different parsing.

A migration to kind 1111 is simply not possible. It would involve the sequential migration of every post, with interaction from every author, to keep the IDs consistent. A half-complete migration would be useless.

For a switchover date, it would be hard to coordinate this. 50% of what, for example? Users? Clients? Who defines the “everything” set?

This could be implemented as a filter optimization, rather than a break. The benefits of kind 1111 for kind 1 posts are negligible, considering that a majority of the data usage from clients come from images, not relays.

Many clients also have a replies-inclusive feed, which users already switch to frequently.