I agree, and it's certainly a good idea; OGL fears are still valid to this day. I think a much cleaner route, however, would be to abandon the chassis entirely. It protects one's long-term IP through unique game mechanics or by using an open system as a base.

A lot of how a game encourages play is based upon the small details that designers choose to include. In 1974, looking at OD&D for the first time, players probably wouldn't think to tap the floor for traps, but a 10' pole is curiously listed on the equipment table. Same with listening at doors, or things like that.

So instead of coming up with something entirely bespoke, companies seem to use D&D as a base not because it serves the game, but because it has lower "buy-in" for customers. Which I think is a shame.