I think it's more than just the size. I use my laptop, 15" MBP 2016, when traveling to keyword and do some minimal editing. However, the very nature of the screen, as good as it is, precludes complex editing. Laptop screens are challenging to calibrate, my 27" NEC with Spectraview is much more accurate.
What I do is export my photos as a catalog from my laptop to my Mac Pro 2013 desktop, this can take a while, but then I have all the keywords and minor edits and I can much more easily work with the files. It is a big timesaver for trips with lots of photos.
This approach, use a desktop machine for "serious" work seems to be the consensus.