I mean keys unlock the door and as has been pointed out Jesus is the door. Every believer has the key to unlock the door it is the gospel message. Unfortunately the RCC likes to burden others and make those keys very heavy. It has nothing to do with the so called Vicar of Christ. Peter was not a pope nor a bishop. He would be appalled that this line of succession has been connected to him, especially when he saw their behaviour.
Let us look at some of what Peter says:
1 Peter 1: 14+
14 As obedient children, do not conform to the evil desires you had when you lived in ignorance. 15 But just as he who called you is holy, so be holy in all you do; 16 for it is written: “Be holy, because I am holy.”
I think he would say that most of those popes have conformed to evil desires.
17 Since you call on a Father who judges each person’s work impartially, live out your time as foreigners here in reverent fear. 18 For you know that it was not with perishable things such as silver or gold that you were redeemed from the empty way of life handed down to you from your ancestors,
Hmm the RCC do not live as foreigners here in reverent fear. The RCC loves perishable things.
1 Peter 2:11+
1
1 Dear friends, I urge you, as foreigners and exiles, to abstain from sinful desires, which wage war against your soul. 12 Live such good lives among the pagans that, though they accuse you of doing wrong, they may see your good deeds and glorify God on the day he visits us.
The RCC does not abstain from sinful desires and it known for its sin. It also syncretize with pagan beliefs, even blessing pagan idols.
“He committed no sin,
and no deceit was found in his mouth.”[e]
23 When they hurled their insults at him, he did not retaliate; when he suffered, he made no threats. Instead, he entrusted himself to him who judges justly.
We have seen how some RCs hurl insults at believers. Also the history of the RCC is it made others suffer, hurled insults, put others to death etc. In Peter's writing his focus is Jesus alone, yet the focus of the RCC is Mary, the pope, its false teachings and not Jesus.
Reading just two chapters of Peter's writings you can see how he would have nothing to do with the RCC and its line of succession. He would be appalled by its behaviour and teachings and false focus.