I think the single most convincing feature that I would like in a conversation app is for there to essentially be two companies with a public benefit charter that said that they cannot have common ownership or management, yet provided the same paid service, developed a common product though open source and had an etremely easy migration between them.

Ideally migration should be easy enough that it would be easy enough to automate a mobious strip subscription where it seamlessly alternated between providers.

If that structure existed it would be nearly impossible for a single provider to enshittify. The sad fact is that no matter how many assurances (often sincerely delivered) have been made, we have all seen instances where buyouts, management changes, or just someone in control going nuts, have turned platforms sour.

Open source is great but as this thread shows, just being open source does not mean functional or maintained.