The fact there are no more promos at all means it’s so easily to be elo inflated. Masters is just an extension of Diamond now and obtainable by anyone. Even if you demote (the generous 4 game shield is even still there), you just win two games and you’re back in it.
Should promos be brought back to combat inflation?
If Riot decides that there are too many high elo players they can just silently adjust the system to award less LP, there is no need to bring back promos to achieve that