T480 also has dual batteries with one being removable. I upgraded the top cover to magnesium, added WiFi 7, upgraded to 32 GiB, swapped from a HDD to a SSD, and changed the motherboard from i3-7300U to the i7-8650U. The only repair I ever did was replace the screen because I messed up once and dropped it. Oddly enough, it supports an eGPU over Thunderbolt 3 and 25W TDP unlocking so it was once used as my compact gaming machine. Mine also has 3 spare extended batteries and a custom external charger for them.
T480s and T490 are inferior compared to the T480's usability of ports and batteries.
T480s and T490 are inferior compared to the T480's usability of ports and batteries.