First among equals is not the same as a monarch, Pope Gregory characterized his office as the servant of the servants of God when dealing with an overreaching Patriarch of Constantinople. The Pope is a magisterial head, much like a principal or head teacher. The bishops are fellow teachers asking for clarity on what the school policy is. I don't see their actions as any different than when Paul stood up to Peter, in fact it was even milder as the 4 Cardinals asked the questions in private months in advance.

What kind of job do you work at where you cannot ask questions, that sounds like a horrible work environment.