Honestly? I don't have much issue with it when it's taken as a standalone incident.
Dolph Ziggler is a 5-time IC champion (well, 6 now). It's perfectly believable for Seth Rollins to lose the IC belt to someone the caliber of Dolph via shenanigans/being distracted by Drew McIntyre and a handful of tights during an open challenge (meaning, he didn't prepare for Ziggler). People can get caught slipping during open challenges.
Additionally ... Ziggler is a IC Champion who thinks he's World Champion material, and he always brings it for IC/midcard title matches. He's a more than capable workhorse IC champ if they wanted to do that.
This is basically HBK/Diesel/Razor from 1994. Just so happens that Diesel helped HBK beat Razor this time. Either Seth gets it back in short order or moves to greener pastures while Drew mollywhopps DZ.
However, taking all the other shyt into account ... they should have just gave it to Elias last night.