Success hides problems though. If through some unforeseen means a competitor were to arise in 5-10 years who happened to have a better UI that works for a wider range of people, then spending 35 years saying “They can’t choose anyone but us! Let them eat CLI arguments!” is going to look pretty silly.

If it would cost a tiny, tiny fraction of their revenue to shore up their UI to make it harder for a future competitor to disrupt them, that seems like a worthy use of money.