This hasn't been the case as of yet. We've had many large companies just pay the sponsorship. Honestly, the problem is not the EULA, it's the need for more flexibility in invoicing than GitHub Sponsors provides today.

To say it another way, legal is cool with it, the challenge now is making it easy for procurement.

Honest question: how would you know if companies stopped using the product as a result of this change? Presumably the only ones you'd hear from are ones that managed to get through the process far enough to complain about procurement (which is definitely another issue, pretty sure GitHub Sponsors doesn't do net 60...)