Not all AI companies are the same.
Some are piling on masses of debt to built capacity (eg. Oracle). Others are just reinvesting the profits from the rest of their company (eg. Google, Meta).
Anthropic’s moat is their best tool, Claude Code.
OpenAI’s moat is the brand of ChatGPT, once the fastest growing app in the history of the world.
It’s possible that open weight models keep pace, but it’s also possible that the investment to train them becomes prohibitively expensive and open weight models cease to keep pace with the large foundation model companies.
Open weight models will keep pace because capable open-weight models are China's strategy for preventing a closed takeover of AI by the West.
I really don't think open models will lose. I think they are cheaper to train because they have to be more efficient than the monstrosities we have now.
There is no theory that says the current frontier models cannot exist in models with 1/100th the compute waste ;). When we start trending in that direction, and oh wow we truly are, there will be no reason for these services. You could run them on your own hardware without serious investments.
The moat openai and anthropic have is them among others have attempted to buy all of the computer hardware for the next two years. That's intentional. They know the only existential threat to them is anyone coming up with a way to do this better than them. It's already happened and it's going to become more and more divergent.