ifilipic16
GeorgeFloydOverdosed said: Match/league reputation does matter, but not that much. The main thing is minutes played in competitive matches, preferably in inactive leagues (though they may have readjusted this again since FM23).

Rough comparison:

21 year old playing 25 first team matches (Div 1), 6.5 match rating, great facilities = +13 CA
21 year old staying at Div 1 team and playing in reserves, 7.4 match rating, great facilities = +4 CA
Loaned to Div 3 (active), 25 matches, 6.7 rating, good facilities = +11.5 CA
Loaned to Foreign Div 2 (view-only), 25 matches, 6.8 rating, good facilities = +14.5 CA
Loaned to Div 5 (active), 35 matches, 7.0 rating, average facilities = +12.5 CA
Loaned to Div 6 (inactive), 35 matches, 7.1 rating, crap facilities = +15.5 CA

One note should be starting CA, if i loan my CA 140 player to lower rep league he won't improve no matter if league is active or not.
Yarema said: Interesting that league reputation has no effect on growth. I guess in testing scenario that could be the case but I'm pretty sure that CA is limited in a league with bad reputation - for example a 200 PA player might only be able to grow up to 150 CA in a mediocre league.

Thinking about this and how i saw my players develop. Could it be reputation of opposing teams is what affects player development. As i go forward with my San Marino BAN i found my players would get stuck at a low CA cap even with 20 training facilities. Something like 120CA when clubs in my league had half a star reputation. Now that they are up to 2 start even my backups go up to 140CA without playing that much in CL.