Agreed UX can be easily copied, but brands are a moat for a number of (granted, psychological) reasons:

1. Status symbols - my Lambo signifies that my disposable income is greater than your disposable income

2. Fan clubs - I buy Nikes because they do a better job at promoting great athleticism, and an iPhone to pay double for hardware from 3 years ago

3. Visibility bias - As a late adopter I use whatever the category leader is (i.e. ChatGPT = AI, Facebook = the Internet)

What you describe sounds more like market power resulting from a monopoly