I mean champions that received buffs to force them into the meta in order become 'attractive' picks in proplay.

From recent patches (9.15 to 9.19) I would say that these champions received buffs with proplay in mind: Fiora, Nocturne, Lucian, Caitlyn, Ekko, Jhin, Lee Sin, Graves, Orianna, Kha'Ziz and etc. From the list I would say that only Orianna actually needed buffs!

It's kinda interesting seeing how most champions in the list are popular and have a 'good reputation' in the community... but Worlds is over now, does the balance team actually care about competitive integrity?

Personally I'm not a fan of seeing already decent but popular champions receiving random buffs when they don't deserve them or how Riot let others rotting because they got gutted on purpose!