For React devs, another library to follow is React Map GL (https://visgl.github.io/react-map-gl/). It’s originally from Uber and became community-led recently.

In longer-term, they’re considering supporting alternative map rendered and I’d imagine MapLibre: https://github.com/visgl/react-map-gl/issues/1248#issuecomment-741992816

Mapbox GL is still a really good library and service — in many ways better and cheaper than Google’s Map solutions, so I don’t think it’s going away in any way.