[2023] Somehow Lions are worse.

Originally posted by Mac: There really is no reason and I mean no reason at all for this to still be a thing. Why Gaijin?

I am sure we already explained it earlier. It's because same vehicle often are placed in different position in tech tree.
In WT you have three positions in tech tree rank = entry, middle and top (in each rank) vehicle. And this affect costs (research, repair).
You need to spend (random) 1000RP to unlock entry XYZ from rank IV in ABC, but you need to spend (random) 1200RP to unlock "same" XYZ but placed in middle of the rank IV in DEF tech tree.