Jugg Tanks are the least desired Tanks in any Ops run. Regardless of how your personal Tank performs. There is a reason for this.
The reason is because they are the most difficult ones to play with respect to threat generation. Many Guardian tanks fail to keep aggro from the Sentinels in one's group.
Shadow tanks also receives their own share of dislikes, and then usually from healers. An improperly played/geared Shadow tank takes a lot more damage than either of the other two tank classes.
Vanguard is the only tank class that's considered to be foolproof.
So you say that you prefer a Jugg on your teams? You say a Jugg is completely on par with all the other Tank Classes? Tell that to almost anyone you talk to in game.
Well played Guardians tend to outperform other well played Vanguards due to the latter's heavy reliance on passive mitigation. Shadows are kind of a special case since they have access to arguably the strongest situational defensive cooldown in game (i.e. resilience) and which sometimes allows them to reshape the nature of certain boss fights.
I'm fairly certain that most high end guilds consider a Guardian/Shadow tank combo to be the strongest general purpose one today.