If they were on open weights, at some point the provider would deprecate it, probably with worse notice And self-hosting would probably have been more expensiv

If they were on open weights, at some point the provider would deprecate it, probably with worse notice And self-hosting would probably have been more expensive unless they had massive volume: Deepseek V3.x would have been the comparable open weight model for the performance and isn't that cost effective until hosted across multiple nodes with large batch sizes