There
are practical considerations to a FF camera beyond the old, tired DoF argument.
I suppose I think a FF sensor in a long-register dSLR has a universal advantage (not the debatable DoF advantage) using wide lenses - 24, 28, 30 (31), 35 - even 50mm and 24~70 zooms - which suggests that photographers who spend a lot of time indoors would gravitate to FF. Wedding, or Studio portrait shooters who can't internalize the 55/1.4 as an 85/1.4 (or don't have the space). Etc.
Sure, Pentax has emulated those FL's with its Limited pancakes but to keep size down they've raised the minimum aperture. Combine the darker viewfinder image with a smaller VF and lower magnification and it just becomes too tiring to shoot all day with APSc when you can do it the old way with lenses you probably already own and intuitively understand.
OK all you EVF dudes - I teed it up for you.