If Google Docs suddenly disappeared, everyone would just continue as usual, except that they now use MS Word or LibreOffice instead. If GPT-3 disappeared, what's the alternative?
I feel like everyone is just playing devil's advocate. Almost every developer I know wants a native API or have the option of taking something out of the cloud. It's why paas died and docker as a service took over.
There are open models, eg. Bloom. Same with Stable Diffusion (open) and Dall-E. Creating these isn’t impossibly hard. Some ML ops company showed how you could train a GPT-like model for like $250k or something.