You could also consider a webhost like Hetzner, on which you can get a bunch of 1 gbps machines very cheap, though you have to manage them yourself.
You could try Cloudflare, but they may well consider it abuse and cut you off (though they like to pretend on HN that they don't do this).
Finally, I know that Google is handing out substantial credits for game developers and this could very well be up their alley.
If you can optimize the download size a bit and swap to a cheaper delivery method, it should become feasible to run on a hobbyist budget.
Unless you set up an alternative you'll get absolutely rinsed through the cost of the instance and then the egress charges on top.
"Cloud Load Balancing is a fully distributed, software-defined, managed service for all your traffic. It is not an instance- or device-based solution, so you won’t be locked into physical load balancing infrastructure or face the HA, scale, and management challenges inherent in instance-based LBs."
Every unique kubernetes ingress resource WILL spin up a NEW, uniquely billed Https LB. Every unique kubernetes service with specific annotations will spin up a NEW, unique LB (internal or external). The author is correct.