Really? What software went from open-source to closed specifically because of vibe-coding? I'd also question how long they kept up their quality... What apps disabled contributions in favor of AI slop? I've never heard of this.
Stirling-PDF and Episteme Reader are solid examples of apps that went freemium, but I know of no product that entirely went paid-only because of vibe-coding. If anything, Stirling-PDF was originally vibe-coded and then added traditional programmers to its team upon seeing its popularity skyrocket, from what I remember reading. I'd be curious to see your examples on the other end.