GAHH DAYM . . . I . . I just realized something!
The day before the Reply Update, I tested Regedit (see screenshot). I changed it to Off, which was on. Then, after I changed it back to on (decimal 1), my Valorant returned to normal, with no issues at all. FPS and ping were fine.
But I'll try these tips too.
Thanks in advance, you guys are the best. Sorry for the hassle!