This scenario would mean major negligence on their part, as they had been with Cloudflare for years. When it was clear their services were costing more than the business plan paid for, that's when they should have been contacted with clear numbers and a sheepish admission that "unlimited" doesn't actually mean unlimited. It certainly seems shady to me that they attempted to make it about a TOS violation, that there's no public information about enterprise level and pricing, and that the second they said they were talking to a competitor they had their data purged. It sounds like a failed attempt at extortion to me.

If you are cloudflare and you suspect they broke ToS you quote which ToS has been broken, you specify which country blocking the customer is trying or has tried to circumvent and you force the customer to either move away or enforce geo-blocking for those countries (or have a separate account for those with your own IPs). There is no reason to cancel the whole account if the blocking is country-specific and there is no way that 10k a month is anyway a sufficient benefit for cloudflare for their IPs to be blocked in a country (affecting potentially hundreds or thousand of customers).

I don't think I particularly agree with this take, but it's an interesting perspective.