This is orthogonal to data caps. We could debate separately if people should be allowed to have contracts with those limits, but the actual problem here is that the ISP is modifying the traffic I requested before they deliver it. In this case it was for data cap notices, but next time it might be for ads or malware or anything else they want to inject.

And if there is a data cap, it should be proportionate to the data bw plan I am paying for. I had a 100mb/s plan with a 1TB cap. I moved to a 400mb/s plan and I still have a 1TB cap. So I can burst faster, but my overall usage is expected to stay the same.

That said, I do most of my downloading on VPS provider, then what I finally want to keep, I compress and pull it down over my VPN. This still doesn't help for things like streaming movies, game updates, etc...

Disagree. Paying per byte is a critical part of making people realize they are part of botnets and to create the only incentives that have a shot at working naturally like pressure against poorly secured smart devices. Unlimited bandwidth just forces everyone behind Cloudflare and breaks the internet.