The price of entry may be higher than Canon and Nikon mirrorless, but the image quality is undeniable. That is a world-class sensor that shares tech with the 8K Venice and Burano. Coming from Canon, there is also the issue of third-party lenses, where Sony has a huge advantage that balances out the higher initial price point.
In terms of the "subsampling," this is 4K/50 from the A1 and it looks incredibly detailed for what it is:
Here is the A1 in 4K/120 (HVEC 200Mbps 4:2:2 10 Bit):
I'm just amazed at what Sony achieves in this little camera and its highly efficient/compressed codecs.