There's so, so much misinformation about this out there.
For example - every US nonprofit starts as a plain old vanilla C corporation, and then applies for 501(c)3 status which the IRS may or may not grant. It's a privilege to be a nonprofit.
The punishment that may be levied on a nonprofit is ... loss of that status and a return to a commercial corporation. That loss of status might have knock-on impacts on things like, say, tax deductions offered to donors, and I guess possibly on corporate income tax to the extent a company's accounting shows a profit. But it's not a thing you're "locked into" somehow and trying to escape. Quite the opposite; it's a thing the Federal government chooses to support financially as a matter of public policy.
oAI had a lot of work to do to get recapitalized like it did, but it was not the non-profit status that was the (major) problem. It was (at the least) the investment covenants made with the Microsofts of the world that bound them; the MS deal was the big thing here.
A corporation is locked into its nonprofit status due to its articles of incorporation and state law regardless of its federal tax-exempt status.
I think it’s generally more accurate to say that charitable assets are likely either locked to charitable purposes or need a fair valuation in case of disposal or wind down. I don’t know all the details here, but I would guess it’s enough of a mess between the parent and the for profit sub that some negotiation was inevitable.