Maybe this helps, there is another thread at Babylon in Mapbox Layer - #9 by Veksi which has a link to deck.gl repo where someone is setting up Harp.gl with MapBox. Harp.gl is powered by ThreeJS and I would guess some of the problems and troubleshooting techniques apply. Maybe interesting to @sharp.
Worth pointing out that now that Mapbox 2 is paid and the free version is the forked legacy version 1 at GitHub - maplibre/maplibre-gl-js: MapLibre GL is a free and open-source fork of @mapbox/mapbox-gl. The paid version has, as far as I undertand, many of the same things in it as in deck.gl. Here’s a blog post explaining in more detail: Our Thoughts as MapboxGL JS v2.0 Goes Proprietary | CARTO Blog.