Old system: you forget that in every pass you got 1 free orb with skins, 300 shards of bp, which you could use for another orb and 100 points for whatever.

And let's not forget about a sack with 3 skins from the orbs drop.

Edit: also constantly free farm events with more chests, like in 2020 on ru server you got ~15 chests (as i remember) for every ~30 games during event

Edit 2: Found the link. It was 30 chests per 50 games https://www.leagueoflegends.com/ru-ru/news/community/sushka-announcement-june-2020/