No. That is taking the rules and writing a lore for it retroactively without changing either the lore or rules once the decision to pair them happens.
Doing so would be creating this lore and either redoing the classes to match the lore then adjust the lore to the mechanics that work or adding classes to make the setting work and adjusting the lore to include those classes.
Another example would be having a rule that "listening is a d20 roll" and a lore that "elves have good sight and hearing" then either making the elf bonus to listening high, the roll for listening less random so the elf bonus is significant, adjusting the lore to say "elves are slightly better than humans at listening" or doing more than one of them.