Lapse is going the extensions-for-features route, cross platform from the start, is more buggy atm, slower progress (doesn't have 3 dedicated experienced devs) but is more accepting of community support.

Zed, similar goals and rust backend, probably has some monetization goals (eventual offering of live sharing code service), and Zed isn't afraid to hardcode features. Like... very hard hardcoded features, to the point that I'm kinda concerned about it. This 5min clip of Theo looking over the source code shows it pretty well https://www.youtube.com/watch?v=ZOYp6-k9HhE&t=1533

The Atom/Zed devs write the most well-documented code I've ever read. Clear variable names, perfect comment-explainations when needed, etc. I wish they would join up with Lapse.