Everyone seems to be assuming that Musk is trying to run Twitter as a profitable business.

I don't think he is. I think he wants to run it as a political influence network.

There's ample precedent. Facebook covertly sold its services to Cambridge Analytica, and both the UK and the US have a number of hopelessly unprofitable media outlets that are heavily subsidised to promote far-right views.

Twitter was a popular and effective (if limited) tool for organisation and dissemination on the Left. I suspect severely damaging that to an election-influencing extent is potentially far more profitable to Musk than selling ads.

If that's the case, he doesn't need to care about building a stable self-sustaining business, only about keeping the lights on for the next couple of years.