If model provider believes they have a better model, it can be a viable bet. But many (me included) started experimenting with other providers because of enshittification from Anthropic (price + uptime). Only to find, that Codex is not that worse in quality for a significantly more output per $.
There are no conspiracies where a corporation has profit incentive. There is perhaps a question of planning and initial intentionality, but the metrics and motivation to continue are clear enough.