The provider framework has been kept MPL, as have the providers, so we will keep being compatible.
We will see what the longer-term future brings, and we'll react accordingly. We also have a bunch of ideas for improvements to the provider ecosystem and their capabilities, but those will go through the public RFC process once it's in place.
Disclaimer: Work at Spacelift, and currently temporary Technical Lead of the OpenTF Project, until it's committee-steered.