You’re assuming he gives a shit about how much profit it’s making.
It’s not a public company, it’s now his private playground to try to get millions of people to see only the “free speech” he wants them to see, and exert political influence.
He’d love to also milk it financially, but that’s actually really hard to do with Twitter.
You could say though as a capitalist he also gets a return on investment by manipulating public opinion in favour of conservatism.
I don’t think he even cares that much about money, except that it’s useful/needed for the things he wants to accomplish.
Unfortunately, the things he wants have gotten steadily shittier and shittier and more disgusting over the last 15 years.