I believe vibe coding in general is a bad business strategy whether you use FOSS models or not because it means your product probably doesn't have any "secret sauce" (leaving code maintainability problems aside). By that I mean a carefully researched innovation that gives the edge to your product. Nevertheless, using FOSS models is clearly better for the reason you mentioned. I believe serious businesses will transition into using AI on-premise in a very restrictive manner (eg: AI only for tests and reviews policy, etc.). We'll once the dust is settled.