I don’t really feel that my 4a slowed down, but the battery is degraded for sure. Battery life was never amazing, but now it’s just bad. So this is why I am looking at the Fairphone: If I could just swap my battery easily, I would just continue using my 4a.
There might be such a future, but I don’t think it will be too soon, unfortunately.
However, your example of the BYD Dolphin has 427km of WLTP range. According to ev-database it has 350km of real world range, about what the meme was stating in miles: https://ev-database.org/car/1919/BYD-DOLPHIN-604-kWh
Or could you point me to a source that says it has 500 miles of range?