IP locations work great for probably a reasonably large chunk of services.
But it's the edges that get you.
I moved home a few years back, connected a new service with the same ISP.
They have an IP pool that is labelled as for one state (Victoria, Australia) but is also used for their services in Tasmania.
So now I have to fight every major website (Google, Amazon, Maxmind, etc) that does GeoIP lookups that I'm not in Victoria, I'm 500-800KM away.
Google was very confused for about 12 months because when I moved I also brought my wifi gear and so it would give me a precise location of my old address because it used wifi geolocation.
But it's the edges that get you.
I moved home a few years back, connected a new service with the same ISP.
They have an IP pool that is labelled as for one state (Victoria, Australia) but is also used for their services in Tasmania.
So now I have to fight every major website (Google, Amazon, Maxmind, etc) that does GeoIP lookups that I'm not in Victoria, I'm 500-800KM away.
Google was very confused for about 12 months because when I moved I also brought my wifi gear and so it would give me a precise location of my old address because it used wifi geolocation.