Not every ISP! Where I live there's an awesome ISP, Sonic, which is pro-NN, and last I heard only offers "best effort" service
which means there's no throttling your link, no paid tiers; if the fiber and hardware can support 10Gbps symmetric, then that's what you get.
Sadly, they're not the norm. And sadly, not offered at my address.
Right
not immune to congestion at all. Unlike ATT fiber, where we had 300Mbps (symmetric I think)...but if you log in to the modem it reported a gigabit link. Starting a download, you could often get more than 300Mbps, but it would slowly fall in line with bandwidth policies.
With Sonic, my gigabit connection would get north of 900Mbps (iperf3), both ways, to a nearby university computer. I miss it.