It won't be photoshop then. It will be shitty, buggy clunky app that costed a (major) fraction to develop but it will also earn a fraction. Companies like MS can afford this ie with Office suite but patience of markets and customers can allow them to go only so far, if ie Excel becomes semi-useless thats the end of Office and big cash cow for M$ (I'd say about time, that monopoly is not good for consumers at all).
This is in a way the same argument that all companies will use just boxed (albeit customized) software. In reality many, ie banks run their own custom software and for good reasons. Wake me up (in retirement) when any major bank decides to run their finances, regulatory stuff and transactions on llm-generated stuff made by underpaid devs like you describe.