To be fair, if the problem is the amount of data that will travel through your connection, there is not much difference between this and a 120MB text-only html file.

So maybe browsers should offer a setting to cap the data retrieved from each individual domain on metered connections, unless instructed otherwise on a domain-by-domain basis?

This is only problem on fast and capped connections which I would guess are rare. On slow connection (and proper browser) you see that it's downloading data, how much, how fast and you can stop it.

4g is fairly fast and generally capped. That is hardly rare.

Oh, you are right. I was under the impression that 4G is something like 2-3 Mbps, which would make the caps somewhat proportional and hard to pass by accident. But I just tried speedtest.net (app) and download speed was almost 40 Mbps. I really had no idea.

ISP offering 100/1000 Mbit connections with a data limit of 2 GB /month is absurd. I think that is the problem here, and not heavy content. Then there are bandwidth monitors ...

I noticed though that the video continued downloading even though I had hit pause.