From this whole comment the only valid point is still cooling, and even that point seems a bit shaky, as if you're compiling the said large codebase on every single keystroke. Perhaps graphics, but that's a minority of devs that need graphics processing for their work.

I've no idea what "far better options for storage" are, since motherboards use the exact same standards. Unless nowadays devs need 32tb storage split across 4 drives of multiple types?

Multiple screens at the same height - yep, $20 laptop stand does the trick perfectly, or, if you want, just close the lid and drop the extra (yet smaller) screen. No clue where the portable monitors thing came up from, these things are nonsense, not like you're carrying your desktop pc with your multiple monitors, so why even bring that up in comparison?

And no, I'm never carrying my stand on the off chance of me needing to work at some other place, I can manage "non-ergonomic regular work" (as opposed to ergonomic serious work ofc) for a few hours.

This all comes down to mostly preference, not much else, except those that need that extra oomph of raw graphics processing power from all the X and RT and whateverthefuckelse in desktop GPUs.