Here are a few more links with interesting discussions about full frame sensors, and megapixels, and much more. 🙂
https://www.lenspiration.com/forums/topic/sensors/
https://www.lenspiration.com/forums/topic/gear-advice/
https://www.lenspiration.com/forums/topic/better-alternative-to-the-7d-mark-ii/
https://www.lenspiration.com/forums/topic/looking-for-new-camera-thoughts-for-sale/
https://www.lenspiration.com/forums/topic/whats-your-recommended-nikon-fx-camera/
Here’s a quote from the last link there, from @jamesstaddon:
The MAIN reason I shoot full frame (and will probably never return to a cropped sensor) is because wide angle is truly wide angle. When I’m shooting at 17mm, it’s truly 17mm, not 27mm.
Secondly, it’s the size of the pixels, like @buddingphotographer mentioned before. The bigger the pixels on the sensor, the higher quality and better noise control you will have.