Cursor also has a large customer base including most of the Fortune 500, talent, and their own coding model and training infrastructure using their data. You wouldn't get those automatically by subsidizing Claude, and the many months or even years it would take to ramp up your own IDE/coding hardness from scratch and acquire customers to match Cursor would put you way behind in a field where the SOTA climbs every month. It's also not clear that Anthropic would let you undercut everyone else using their API; they could cut you off at any time. That would be a very precarious position.