The difference is that releasing the model for free doesn't have ongoing cost for the company. Providing cheap tokens is very expensive - specially if you don't have access to the latest transistor node chips. So I think the parent comment is right, there's something else at play allowing DS and Xiaomi to offer these nearly free tokens.
I mean there is a minor moat. Most people don't enjoy switching providers or models. If you can get people to trust you'll stay near frontier, they'll stick around even when you aren't the best. Claude is a prime example of this
There is no "moat" for me.
Using the standard chat applications as a normal conversational/question has a little bit of moat as its able to cross reference existing conversations, but I disable that mostly anyways to prevent as much data retention as possible.