My observation is that Opus is chronically capacity constrained while being dramatically more expensive than any of the others.
To me that more or less settles both "which one is best" and "is it subsidized".
Can't be sure, but anything else defies economic gravity.
Or Opus is a great model so demand is high and the provider isn't scaling the platform. I agree something defies gravity.
Also that's not accounting for free riders.
I have probably consumed trillions of free tokens from openai infra since gpt 3 and never spent a penny.
And now I'm doing the equivalent on Gemini since flash is free of charge and a better model than most free of charge models.