I traded my Eden Metro for my 800RB a dozen years ago, so I can comment. Part of it is that the calculus of how heavy is too heavy has changed. The Metro is a heavy combo, full of features, but with a 1990's sounding scooped cabinet that defines its tone.
That's the other part -- the tone. The Parametric EQ seems, in retrospect, best designed to decide what kind of scoop you want. The Metro/XLT tone is of an era, and not really a classic.
The 800RB on the other hand is a classic. It's still on the lighter side of class A/B solid state amps, and having the portability and flexibility of a head, is less likely to be obsolete. I sold mine off in favor of a 700RBii, but mainly to skip out on likely upcoming maintenance with a few scratchy pots. The 700RBii responds and sounds basically the same.
Some solid state amps are true classics and will see long use, just like some of the Ampeg tube gear. I've been to giant festivals within the past decade and seen 800RB's in the rack (Levon Helm's bassist at the Vibes in 2011, iirc)
John Rider of Max Creek still rocks his Eden preamp -- the same preamp as the Metro basically. Lesh was using his forever, not sure what he plays now.
But the old Acoustics aren't in use in the same way -- GK's eighties stuff seems to be the inflection point of solid state obsolescence.