The public IP location is not precisely your location because your IP address does not convey that information at all. Services that locate an IP guesstimate based, mostly, on what range your IP is a part of, and what public data is available about that range.

I'm not sure about Spain (pretty confident it is the same, only a capitalist hellhole would do what you suggest), but in France and the Netherlands at least, your IP (the one a website sees) is always yours and yours only, not the IP of some ISP server.

If you can open your ports in your router and access them from the internet, then your public IP is yours. Most people can (even with a dynamic IP). If it was an ISP server, you wouldn't be able to.

The thing a european ISP usually do is assign a dynamic IP, so that while your IP is assigned to your home router and yours only at a moment in time, it will likely change the next day, and will always change on a reboot of your router. But it still is your router's IP at that moment in time, not a random ISP server. IPs are not physically assigned to a device

My home IP is mine, fixed, and I can verify that it is indeed my router. Yet the location of it according to locators is the other side of the country. The location locators give you for your IP being different to your actual location is not a proof that your public IP is not your actual home IP at all. And that is because an IP is not tied to a location and only your ISP can tell the location of their IPs.