I still didnt get shadowban as others claim in this post, or at least i managed to replicate it.
I used 2 accounts to check, leaving my main one untouched; a new account, 0 old days, and my alt, with 2 months.
None of them got shadowbaned until trophies reset, where my young account trophies no longer counted.
Looks like playtime is taken into account
Maybe they also look currency, but in that case, devs should check any player that already has 50K trophies in first PvP day.