Sonic has 10GB symmetric fiber with no data caps in parts of the Bay Area. The best ISP!!!
Edit: Just checked and for 10 G it would be about 10 euros and for 2.5 G - 9 euros, that's a very good upgrade, probably they assume that most users won't take advantage of the full bandwidth.
I definitely don't have any way to take advantage of 10g, that's for sure. I guess WiFi 6 might be able to make some use of 2.5G. I'd upgrade for 1 euro more if I was you.