Anthropic ARR went $1B -> $4B in the first half of this year. They're getting my $200 a month and it's easily the best money I spend. There's definitely something there.
It makes me perhaps a little sad to say that "I'm showing my age" by bringing up the .com boom/bust, but this feels exactly the same. The late 90s/early 00s were the dawn of the consumer Internet, and all of that tech vastly changed global society and brought you companies like Google and Amazon. It also brought you Pets.com, Webvan, and the bajillion other companies chronicled in "Fucked Company".
You mention Anthropic, which I think is in a good a position as any to be one of the winners. I'm much less convinced about tons of the others. Look at Cursor - they were a first moving leader, but I know tons of people (myself included) who have cancelled their subscription because there are now better options.
For the time being, nothing comes close, at least for me.
User experience is definitely worth something, and I think Cursor had the first great code integration, but then there is very little stopping the foundation model companies from coming in and deciding they want to cut out the middleman if so desired.