Spoiler:
I usually solo queue with my wh and often get 12vs12 cities (although most of the time it's +-2 on either side, which already tips the balance of the instance). The instances were a hot mess most of the time, because they were a gathering of all the misfits that didn't fit the meta groups. The team composition was usually all over the place. Sometimes you're lucky and a tank or two take a wrong turn and end up in your instance as well
If you look at the order chat while you can queue it's either a wb looking for tanks (and sometimes healers) or rr80+ dps (even SL/WL) with sov gear looking for groups. Good luck finding tanks and healers for a 2-2-2 12 man that would like to take your non meta, non sov gear, sub rr80 dps char over some rr80+ meta char. It's possible, just like balanced and fun 12vs12 solo queue cities are possible. But it's extremely rare and nothing you can rely on. Which in the end makes progress for those classes far slower and more painfull than for the meta classes.
Aside from class balance problems: Allowing to get your gear in more aspects of the game would also help with the problem that a lot of a EU players rarely even see cities, because they can only play at EU prime time