>"I didn't know that a modern laptop could drive 2 4K monitors. This is good news."
Not any laptop but some do. It even does it while driving its own built-in monitor but I do not really use it.
>"your laptop setup is indistinguishable from a desktop"
you got that part right
>"your setup is even less portable than a desktop"
Nope. When I am out of my main office for whatever reason I unhook said laptop from all the cables and it works off-site including all my development environment. If my stay away is extended (working for a month in ocean side cottage for example I also would take one of those monitors). I just do not run production servers/databases/etc on my laptop ;). Btw my laptop soon transitioning from 32GB RAM to 128GB RAM as to give me more flexibility with the databases.
Worth case I can still access my workstations/servers remotely using SSH or NOMACHINE if SSH does not cut it. Since I have very fat internet pip it works just fine.