The 8-speed is a heck of a lot better than any of the ones before it in trucks; 4-, 5-, 6-speeds are grenades with the pin pulled. 4xRE is ok after it's been rebuilt with some upgrades.
I suppose the Pentastar V6 in a Ram would work at sea level, my mom has a 2014 300C with the V6 and 8-speed and it was pretty quick up to about 70 mph at 5000' elevation but that's at least 1000 lbs lighter than a Ram. My dad recently got a 2021 Ram 1500 with the 5.7 and 8-speed after moving to TN and driving it is a hoot, hauls *** for how big and heavy it is but it'll probably never tow anything. My mom just moved out to TN to live with my dad, I'm curious to find out how much power her 300 picked up from the elevation change.