Going to got against the naysaying here. I understand that it might not follow best practices, but I can see a lot of benefit to this.

Imagine I want to test something fully offline, but my app was built using OpenAI's API's ideally I can do a quick swap now and have an offline compatible model.

Additionally, let's say I want to offer a free version of AI to my non-paying users, but for my paying users I can afford to allow them to use OpenAI, this will allow for an easier swap without having to rewrite everything.