Some of these are huge.
Note that due to the hinky way WordPress processes bulk image uploads, these do not generally appear in the order of the original videos.
These first ones are from the 4K YouTube video mentioned in this post: YouTube Video Shot With The Insta360 Camera.
These screensnaps were done on an iMac at an Apple Store. The iMac in question had a 5K screen.
That means there won’t be a pixel-for-pixel match. But given the way YouTube processes videos, that probably doesn’t matter and might be even impossible to get.