OP said a fully saturated gigabit link, which generally means you pay for transit ("size of the pipe") rather than "stuff pushed through it." I haven't been in the market for a long time, but 5-10 years ago the price was on the order of $0.50 per mbps, so $500 for a 1000 gbps ("gigabit") link. Usually you buy this with a dedicated server or colocation. You wouldn't want to host this in the cloud because they price gouge you on bandwidth by charging for stuff through the pipe.

And that's if you truly expect to saturate it. If you just want to take the risk and go for oversold fiber, you can pay some nominal price for "unmetered bandwidth" (with the caveat that if you're saturating the pipe, your host will probably make you pay for it eventually).

That's ridiculous bandwidth pricing. you can get unmetered gigabit at Hetzner for €20 per month. Need 2 Gb? Order a second server.

Do you think this is an important point?

He was using Hetzner and says it was costing him $200/month. He then had to spin up a second server, presumably increasing the cost, and it was still struggling.

From there traffic doubled, and he moved to Cloudflare Workers. And then traffic 30xed.

I suspect it's more about request count (>300k per second) than raw number of bits.