1) Yes, I watched the video. Complete with the presenter constantly hedging his claims about "not quite this" and "not quite that". As well as a couple of "Can work around this/thats...".But half a dozen. That’s just ridiculous. I can do that only my iPad in matter of minutes. It is all raw as well on my d810 and d7200. Did you even view the video? Review and marking of photo is much faster than a MacBook Pro or any laptop or even a high end desktop. Lightroom on Mac and windows is a dog. I can attest it is much faster than my MacBook Pro and also surface Pro 4 when I dabble with it a while ago. The fans would be go full blast and processing ground to a halt at times. Not tested a high end desktop so cannot comment on that. I’ll leave it there.
Working around things is not something professionals put up with for long.
2) If you want to convince me of what you say, take your Nikon 810, mount it on a tripod behind your shoulder, and shoot us a nice un-edited video of you doing a complete import, culling, and color edits on 150 24MP RAW images on your iPad Pro. Otherwise I simply cannot believe your claims.
3) My 15" 2017 MacBook Pro puts the lie to your claims of it being slower in Lightroom than my iPad Pro. It flew. The parity in preview speed from the card disappeared when I copied the images to the MBP's SSD first. The fans didn't even rise above a whisper while editing.
As for my new iMac Pro, let's just say that there is no possible comparison.