You should be able to change gear in the middle of Solo Shuffle and RBGs. I get that people are going to whine and moan about the fact that “It’s not fair, because that one dude found some exploit with a PvE trinket and that’s OP”, but that is LITERALLY WHAT THIS GAME IS ABOUT.
This is just another barrier that takes the fun and creativity out of this game. On top of that, if you do accidentally forget to switch out a piece of gear, your entire team is effectively punished for the entire game. I forgot to switch out of my PvE set the other day, and I was wondering around this Shuffle BG with -50% HP. I could do 0 damage, and my healers could do nothing to keep me alive. It made me worthless.
This adds virtually zero benefit to the game, and it hurts teams all the time that have members that forget to switch out PvE pieces.
(Of course, this problem could be mitigated if this bullsh!t PvP gear scaling system went away. We had great gear back in TBC, WOTLK, Cata, MoP, and WoD, there’s no reason it should be this convoluted to deal with now.)