In 1989 I got my first DECstation 3100 (Ultrix) and had a similar reaction! I never warmed to the Suns quite as much back then, but did like the Sparcstations of the later 90’s.
I admit, I still prefer the sharp cornered rectilinear windows of the older systems. Old style Gnome, Win2000, those are my comfort zones. These newfangled rounded themes with drop shadows drive me crazy.
Good old Ultrix. No compiler. Either use VI or Macro-11 Assembler.
I actually went to DEC’s school in Mass. to learn both.
I had several PDP 11/70’s running it. BUT no GUI. All we had was VT-52’s and a DEC Writer form feed paper terminal!