Lightroom is degrading my pictures

TL;DR

My JPEGs look like crap when I'm in lightroom but crispy clean in any other program. Why?

When I import pictures into Lightroom Classic, the image I'm editing looks significantly worse than the original file and the exported file.

Before you assume that I don't know how cameras or Lightroom works:

1) I know RAW files can often times look worse than their JPEG counterparts before editing and that every RAW file has a JPEG preview. It's my understanding that raw files contain more information than JPEGs and can look too bright or too dark but still be recovered because the camera hasn't changed any of the data.

2) The files I'm editing were JPEGs before I imported them, not RAW. They were shot as RAW files but then imported into lightroom and converted to JPEGs and then sent to me.

3) I know that lightroom displays unedited RAW files rather than the JPEG preview in the development window and I know you can't stop this function.

-It seems to me that it should be impossible for Lightroom to know that my images where at one time RAW files because the JPEG compression would have removed most of the image data, AND the images were imported as JPEG files. This should get rid of the possibility that the program is showing me a RAW file.

-I know that images can be degraded due to too much "motion" ( Importing, exporting, uploading, downloading, and re-importing) but the files I see in the file explorer, not Lightroom, look clean and dynamic with all the detail I'm expecting, so the problem is coming from Lightroom.

-Lastly this issue happens also in Photoshop and Lightroom CC

Is there any setting that I'm missing?

Is it possible that Lightroom IS displaying a RAW file even though half or more of the image data isn't there anymore?

     - I think this is the case and because of the file compression my "RAW" files just look like poop because data is missing