if that were not true, they wouldn't be in business.
Why? They are not loosing anything while developers are gaining time using their website.
They had 66 million dollars revenue in 2021. They have about 20 million registered users (and much more unregistered, and that's revenue not income, but let's forget that). Do you really, honestly feel, that SO doesn't save you $3 worth of time per year?
Because if he's able to help anyone on SO, he very likely profited many, many times from free access to knowledge there before he got to this point. Given activity of average user he probably gained orders of magnitude more than he given.
I find rambling about money and compensation in such context distasteful.
SO provided platform which, while not perfect is used by millions of people. They aren't overloaded with ads and dark patterns as many of the clones. If it's worthless, why people are using it instead self hosted blogs for example?
Why do you go there then? If you don't, they won't get their $3 out of you and universe is in balance again :-)