If you live in a city, please also narrow down the area.
This offering is available from digi.ro pretty much throughout most major cities (so city area doesn't matter unless you go outside, into suburbs and villages - not sure how far the fiber penetration reaches).
They announced 10Gbps a few months ago, for only a 25% price increase (someone else linked the announcement already) - but I'm still on the waiting list, and I'm not sure what their deployment progress is like.
I wish I could offer real numbers for 10Gbps - for 1Gbps I remember getting:
* >900Mbps download locally (P2P, fast.com, etc.)
* 300-500Mbps both directions, across Europe (e.g. to Hetzner servers)
* not sure about intercontinental, but I suspect latency could be more of a problem there, depending on your usecase
(Frankly, consumer networking equipment has been getting in the way of reliably maxing out what the ISP offers, in a multi-device environment, and I've been procrastinating getting more professional hardware since the difference is mostly only visible when measuring it explicitly)
As for affordability: you can live here decently for around $1k/mo, maybe a bit more depending on rent, so if you have an international source of income (or a good chunk of savings), you could easily spend years here.
(Most of my monthly costs go towards food, and I don't have good points of reference for that - I can't remember what it was called, but there was at least one website for breakdowns of living costs in various parts of the world)
One downside is you may need to learn a bit of the language, depending on how much you need to interact with the average person that might not know any English (but this has gotten easier with e.g. using delivery during lockdowns).
OTOH, English has been permeating a lot more, starting with millennials, so you could get lucky.
Have fun! (though realistically there are likely more convenient options)
https://fiber.salt.ch/en/home/internet
It is possible also to get 25G for the same monthly rate, but you need your own hardware.
It how ever is not the cheapest country in the world, so it somewhat depends on your definition of affordable
Sometimes a git clone can take a little while. Streaming a 4k movie is about 0.02 Gbps. Latency matters for gaming but what else?
I suppose you could do things that normally wouldn't make sense like having a fully cloud remote development environment. I tried out RubyMine's Remote Development (beta) and I thought "who could possibly use this with the entire JVM of the IDE running in the cloud with only the graphics displayed locally?" I think I found the crowd.