{ Multiple people in household each having multi-party high resolution video calls | band practice | data manipulation collaborations | 4K TV on demand } can suck up the bandwidth when the priority is smooth real-time with low interactive latency.
It's not always going to be peak demand, but it'll be noticable when everybody piles on at particular times of day.
TBH I have relatively low bandwidth most of the time and don't notice download speeds at all as I queue the things I want and return to working on what's in front of me.
Sure, but the OP talked about being happy with a 10Mbps link.
I think a lot of modern households might find that constraining, even if a 10Gbps link was massive overkill.
There are two orders of magnitude in between of course :)
Personally I found that going back from a 1Gbps link to ~100Mbps has felt a little sluggish, particularly when downloading games. It's not a huge thing, but being able to get that new game pretty much now was great.
Edit to clarify: I cannot fathom live collaboration over the internet when even 15 ms lag is annoyingly noticeable (10 ms latency with a midi keyboard seems like the cutoff for me personally at least).
It's not always going to be peak demand, but it'll be noticable when everybody piles on at particular times of day.
TBH I have relatively low bandwidth most of the time and don't notice download speeds at all as I queue the things I want and return to working on what's in front of me.