Being consistent and playing well in plat 5 has been punishing me as worse as ever

This last month one too many times( not even just thanks to the trolls/some dc & afkers) where I can have best CS/kda ingame or almost best, as teammates cant help but feed atleast one enemy by mid or being to give up and play worse. Doing my main 2-3 adcs, and trund to consistently as ive done from silver to almost plat 3 this season , yet I feel like I been cursed suddenly aftter the third time hitting p4 100LP, being put on the "worse" side way more than I have been before, and more than statistically I should be. Getting an average reliable team and especially twice in a row even impresses me , while It would be average to get that or better for months previously

edit: A friend who reached plat 5 on an account and on others is trying to reach it too, has suddenly stopped being able to win/impact games as much as well these last weeks thanks to, "boosed teamamtes" and an increase in boosters/smurfs hes been versing.

Someone else I know who actually reached mid plat 3, and who like me usually never drops but only eventually climbs, also mainly thanks to in his words "teams" suddenly fell to low plat 5 almost demoted this very last week as well.