One of the best purchases I ever made, at a lovely 89ppi
The issue with going beyond
~90ppi is that too many VST/DAW/Apps aren't ready to support it yet (no proper scaling).
I look forward to the day when I can run a 16k 48" monitor with VST/Apps that scale via vector graphics, but in the meantime ppi is a more important consideration than resolution IMO.
My XPS 13 has 276ppi so, while the resolution *might* look a little sharper than my 50" monitor, it's not even close to worth dealing with the hassle of getting everything to scale properly.
That being said, I'm looking forward to vector Reaper some day