Nonprofit is a just a facade, it was convenient for them to appear as ethnical under that disguise, but they get rid of it when it is inconvenient in a week. 95% of them would rather join MSFT, than being in a non-profit.
Iirc, the NP structure was implemented to attract top AI talent from FAANG. Then they needed investors to fund the infrastructure and hence gave the employees shares or profit units (whatever the hell that is). The NP now shields MSFT from regulatory issues.
I do wonder how many of those employees would actually go to MSFT. It feels more like a gambit to get Altman back in since they were about to cash out with the tender offer.