In the washup after the OGL debacle, and the cost increase of bboks, WoTC affirmed that they were still going to produce physical print books as long as it was financially viable.
These are only the beginning step in turning a supertanker, but the mimicry of the games industry observed by a OP does indeed set a direction of travel - one that will eventually likely end up with no books - or more likely, limited run, collector's edition books at double or tripple cost - with the rest being available with the WoTC season pass.
Speculative? Yes. Unlikely? No