Lag

So i've been playing league of legends for 3 years now, in this time i did some changes in my pc setup, upgrades and more, even tho many players experience lag issues, with every update or something new in game, my fps drops, little by little with every update, i mean for real... i got higher frame rates in PUBG on high setting, that game really needs alot of resources but league is starting to get heavy, my friend when started playing league in season 6 he was playing at a framerate of 120 and now he is happy if the framer rate reaches 30, just 30, riot should do something about it as they said WE OPTIMIZED THE GAME TO WORK ON EVERY POTATO my potato runned league in 300 fps around 6 mounths ago and now i only get maximum 60 (no vertical sync enabled).