I guess that could be a thing, but, that puts them in competition with the people who they might want to be their customers, whereas I don't necessarily know that they would see other tech companies as customers unless they were super interested in partnerships.
According to "the normal progression of companies" though, you might be right because after a company has becoming big enough and exhausts consuming its own market, it often expands into verticals - we've seen that with traditional big 5 consulting companies or IBM, where they expanded into "working embedded with their customers on their problems directly" many years ago, and now every company in the industry approaches it that way.
That is corporate partnership and field work, not so much consuming the other person's work/business... whereas I could see them just consuming the OS because "it's no big deal when you can do everything you need with AI".
But I take your point.
If Microsoft or Google's AI is killing it, and it's built into the OS, how will Anthropic or OpenAI compete unless we run into the same old antitrust/competition issues with OS?
At that point, they might just say - "fine, it's easier to just have our big AI brains and money make a new OS we control and we can compete too."