So, I feel very not-so-smart but I just restarted my MacBook Pro after probably many days and it's working just fine. It is fast again. My bad.
Note: The issues I was facing after the update was an overall slowness and occasional stutter in the animations/graphics. But now after a re-start it's gone. I should also note it wasn't just a re-start. It was a turn off, let it rest for a minute, then start again.