by “matrix chat 3d like things” do you mean https://thirdroom.io?

It would be super easy to build something like this on Third Room - and then get e2ee and decentralisation etc for free :)

Yes! I am trying to recall what was mentioned that can make assets for this.

It software / web app that work with "glTF Models"? More than that?

I did 5 minutes of digging and not sure.. is it unity level of software?

I had some things bookmarked I wanted to make stuff with a while back.. was it Daze3d?

I'd love to see a list of things that can work with this / export to this (matrix usable 3d).

Unity can make glTF for it (as can Blender or anything else that exports glTF). The unity pipeline is: https://github.com/matrix-org/thirdroom-unity-exporter