It highly depends on where you live.

I can get gigabit for about €32,50 a month. 2gbps for about €40. Unfortunately, the cheap ISP that offers these rates doesn't have IPv6 so I'll stay with my current one. €70/mo would get me 4gbps symmetrical with another ISP. All of those include a WiFi 7 capable router, of course.

Prices have increased, but high prices are a local problem. The €35 price for cheap gigabit would equate to about €20 in 2000, so I think prices have stagnated alright, but speeds have evolved a lot since then.

Kinda off topic, but I'm staying on a 500 mbps pipe for now... simply because I don't see the reason for more.

I could get up to 2 Gbit by making a phone call to my curent ISP but why?

May I ask which country that is?