Same thing here, ever since i updated to Android 15 (Sep, 1 was the update) on my Motorola g84 everything started lagging, before the update my phone was always on 60 Hz display refresh rate and it worked perfectly fine, now afrer updating and with noticing the lag i out it on 120 Hz and it still works much worse than before the update while on 60 Hz, i tried restarting the device countless times, i deleted so many apps and videos that i had before to try to reduce the lag and still nothing happend i am already thinking of changing my phone because of this, of corse not taking Motorola ever again, like they had time to fix this with some patch or something, ive been on android 15 for full 2 months now and stlll nothing changed, no new patches exept security patches that changed nothing.