I don't think you get to claim PR credit for advances in ML unless you publish. In general, for R&D, IMHO, you need to publish. There's product R&D, and there's fundamental R&D. If you make an advancement in something fundamental, but that helps your product, then publish it. If it is specific to your product only and can't be transferred elsewhere, then maybe it's ok to keep it secret.
Apple and Google's competitive advantage now arises from scale and path dependency. I think they need to let go of this idea that somehow they derive a competitive advantage by keeping these things secret. The Open AI community is going to advance at an accelerated rate regardless and IMHO, it's better to be part of it than to be seen as a kind of parasite that consumes public R&D, but doesn't give back improvements.