I have to second the view of CharlesN. in spite of your careful rationale, Mark.
For me, there is also one other factor that I find of real importance, though others in the Mac 'community' and Apple themselves seem not to see it as significant. What? - Well, it is the screen size.
I have used a laptop as a substitute desktop for a long time. Originally, I moved that way because it allowed me to take my work with me when the cost of portable storage was prohibitive and cloud based options much more limited than today.
I also utilised that fact that the laptop gave me a limited but none-the-less useful security from power outages, in effect providing me with a free UPS whilst I operated on mains power.
However, my work requires a lot of screen real-estate, particularly as my eyes are not good and I really benefit from using a larger font than would be usual for text work. As I continually work with spreadsheets and databases, that becomes particularly important.
So, the availability of a 17" screen on the MacBook Pro was brilliant for me and I was very disappointed with its demise. Indeed, I still have and regularly use a 2011 MBPro 17", the last of its line but, although slow by today's standards has more than repayed my initial investment.
The advent of the newer 16" MBPro was therefore very welcome for me and surely there must be many others or am I really one of very few?
I must say, too, that I don't empathise with the whole trajectory towards smaller and thinner that occurred over the last decade or so. There also seems to be an irony in that, in many case, particularly where mobile phones & monitors are concerned, there seems to be a resversal of that trend. For me, that's a very fortunate irony.
And yes, I know, many will say that the 17"" laptops were just too big and heavy to carry around but, as I said, mine gives me the best of both worlds and although I am now aged and only 168 cm tall and not particularly 'tough', I've never found it too onerous to carry. The ability to easily move it from place to place, even within a building or home, and without the risk of screen damage or the necessity of mains power, has more than made up for any 'less mobile' factor caused by larger screen size.
Thank you, anyway, for your writing. I much appreciate the insights and views you give.