Converting meshes from one game to the other still has to be a batch process, there's no way someone is going to convert so many individual meshes by hand even with the import and export tools that are available, and which now support collision notwithstanding.
So we'd still need a max script to do this. Not saying this isn't possible, but I think there are still quite a few technical hurdles which stand in the way of doing this for all meshes.
The fact that Bethesda released tools at all and which support collision is greatly edifying and I don't think pursuing this idea would be possible at all without them, but it doesn't change some realities like (for instance) needing to also convert, probably by hand every texture in the old games used by those meshes, then supplying materials for all of those meshes.
Anyway, it's something I'd be interested in just to see how far anyone could take it.