Media Intelligence Analysis
I don't when this was introduced, but Premiere now has an AI powered application running in the background analyzing all of your clips. I first noticed this when Premiere started to bog down and run poorly. At first, I didn't know what was happening and started looking through my computer to see if I unexpectedly ran out of storage space or had other apps hogging my RAM. Then I noticed this icon in the top right corner of Premiere twirling, like it was working hard. I thought, what is this? I clicked on it and found the Media Intelligence Analysis window. It was working in the background to analyze my clips, I guess in order to make them easier to search for by using AI? In all honesty, I haven't researched the purpose, usefulness, or lack there of, of this add on. All I know is it seriously bogged down Premiere!
So long story short, if Premiere suddenly starts running like crap, go into Settings>Media Analysis & Transcription and turn it off. Problem solved.