Videos Exported for YouTube look like crap

I have taken a number of videos with my GoPro Hero 6 camera and edited then exported them in Shotcut for uploading to YouTube. When viewed on YouTube they look like crap. They are very pixelated from the very beginning of the video, and then clear up a little way in but never get very clear at all. I see many people upload from GoPros with lower original resolution with much better results.
Here are my two videos:
MMM 2 Down In 2 Seconds
Corgi on a Bike
The first was shot in 1080 @ 30fps
The second was shot in 2K @ 60fps
Both were exported with the YouTube presets and then uploaded to YouTube.

Help! I’m going to Alaska on my motorcycle for two months this summer and would love to be able to post great videos!

Didn’t you review them before uploading to YouTube?

BTW: The first vid is only showing as 720p

Check your export settings.