If you're not willing to pay for bandwidth you're not a legit customer.
>"I was already paying $200 a year [...]. Her quoted price: $3,500 a year. She was given a week to upgrade her content, decrease her bandwidth usage, or leave Vimeo.
A week's notice for a 17.5x price hike you unilaterally declared? That's not what you should do to such a customer, ever. To me, that's either a shakedown, or a deliberate step to make her stop using the service, e.g. because such "small" account are no longer worth your time, or you try to be a b2b business now, and those "small" customers do not fit with that image, or whatever.
If something changed for vimeo that increased the their own expenditures over night, then I'd have a little more understanding for them. But that's not what they said or even hinted at happening.
If they're not willing to pay a hefty premium for it? I don't follow your comment, buddy. They're already a paying customer paying what was asked of them.
Why would you not just use Cloudfare Stream or another option and save roughly 40% of the cost?
Also services like cloudflare stream/bunnycdn stream/mux are fairly recent.
Another issue is reuploading of all the media. It's not that easy to switch. But people will flee to some other solutions.
However, it's essentially the same service otherwise. Point your customers or business partners to a URL and they stream it from there.