Doesn't matter. Regardless of what Unity said their "Enterprise" plan was, it doesn't matter.
B2B deals just work differently since both companies have more at stake. If a company like EA used Unity, there is no way Unity would want to lose that contract and EA couldn't afford to drop Unity. Large companies will likely go through a few short renegotiation meetings, if that.
Plus, lawyers. If Unity even tries to force this on its larger customers, they are going to be hauled into court and most likely lose. When they lose, Unity will likely be liable for court costs as well.