Well, technically it is a "company" already as it is registered formally as a non-profit. They have income (sponsors) and paid employees.
To my eye, this change does not appear to be driven by a change in corporate governance or profit motive.
They explain that the change and the timing is driven by two things.
1 - The burden and of processing public contributions has increased with the rise of AI
2 - They need to focus and stabliize the code base in preparation to introduce a public alpha
Those reasons ring true enough for me that I do not need to go looking for other motivations. I do not like this change but I can see why they would.