It would have been more helpful if the full-res image links were posted underneath each picture. The small-sized samples embedded in the review are near useless to discern the differences.
That said, the cameras on both are excellent and it's really down to personal preference which one prefers.
I'm not sure about that. Is Instagram full res? Most people view photos on their phones nowadays. Because you're right; judging by all results shown, both cameras are pretty excellent. So it's basically down to which latest-and-greatest OS one wants to use.
Someone else asked if people were trying to be award-winning photographers, and I think that's part of it. I'm sure some award-winning photographers use these cameras, and I'm sure photos taken with these cameras win some awards, but most award-winning photographers reach for an actual camera to shoot with. The photos in the OP are nice, but they're not going to touch an a6000 with a good lens, much less a higher-end set up.
All that said I'm looking forward to seeing the pictures folks take with these cameras, and higher end mirrorless gear. On Instagram. On my iPhone XS Max.