We have introduced (or more like rewritten) an API in 2022.1 which allows you to much more efficiently draw many meshes. See this forum post for more information New BatchRendererGroup API for 2022.1
It’s not perfect. You will still get a separate draw call for each mesh of course, but you can skip a lot of layers in the unity engine. The downside is of course that you will be responsible for setting up a lot of things yourself.
We are hoping to land something like MDI for this interface in the future.