1Gb/s I can see, but 2Gb/s and higher just makes me giggle. How many people have 10Gb/s switches, WiFi access points running 802.11ax, or even know how to set ax up to get even 1 Gb/s WiFi throughput?
Then you get into application performance. It's part of what I did for 30 years. Very few internet users need 1Gb/s throughput and if they do it's always for moving large files. I saw businesses with 100Gb/s internet and would congest it from time to time, but they had tens of thousands of sessions and were doing SAN replication.
It's just a myth that if you get blazing fiber internet speeds, that your gaming will perform better. However, confirmation bias is a powerful tool to justify > 1Gb/s speeds.