It's probably just a relic of tech entrepreneurs being programmers rather than businesspeople, but there certainly is a real aversion to just boring, reliable profitably over time.

This is it in a nutshell, without any "late stage capitalism" nonsense.

Reddit, like Twitter and other prominent tech companies, was supported largely by outside investment. The company didn't make a profit, but investors continued to put money into it in hopes that it would eventually net them a return. Low interest rates make investment capital easy to come by and relatively low risk, but higher borrowing rates have dried up a lot of that funding. This forces the company to find other ways of sustaining itself.

I don't think there was ever any illusion that reddit or Twitter were operating as charitable organizations, or even as non-profits.