Benedict’s resignation should not be all that surprising. He has maintained that a pope can resign, and canon law provides for it.
Despite his reputation as a hard-line, Ratzinger expressed discomfort with the tendency to idolize the pope, culminating in the rock-start image of John Paul II. At one point Ratzinger said that the separated Eastern Churches would only have to acknowledge the papacy as it existed in the first millennium, when it was not all that important.
In their battles with secular and totalitarian states, popes put the focus on themselves as the locus of unity in the Church - ubi Petrus, ibi Eccelsia. This may have been necessary to prevent the church from being taken captive by nationalist and totalitarian governments (as has happened with a large segment of the Catholic Church in China). But such a focus distorts the papal office.
One result has been an unrealistic expectation about what a pope can or should do. The impression is that the pope can by his own will change whatever he wants in the Church, including the moral law. He could allow priests to marry, allow women to be ordain, say that contraception, abortion, and homosexual acts are not sins, etc.
Maciel told the seminarians he abused that, of course while homosexuality was wrong, the pope had given him a dispensation from that law because of his health needs.
Even when it comes to disciplinary matters, popes should not and generally do not make changes without the consensus of the church. The popes who declared the dogmas of the Immaculate Conception and the Assumption canvassed the world’s bishops and received many requests from priests, religious, and laity to declare the dogmas.
Even a change in a discipline such as celibacy would require the consensus of the world’s bishops over a reasonable period of time.
Benedict has done more that any pope in centuries (probably since Pius V) to end sexual abuse in the Church. He has not done enough, but he has done more than most bishops, priests, and even laity want. One reason the Vatican did not encourage bishops to discipline abusive priests is that the laity screamed whenever their favorite charismatic, narcissistic, abusive priest was disciplined. The bishops saw how the laity reacted, and so did the Vatican.
The responsibility for tolerating abusive priests is shared by segments of the church; those who tried to end it were often marginalized and rejected, because abusers are very popular- that is how they get access to children. In such matters, the papacy, the episcopacy, the clergy and laity all failed, and the children were sacrificed to a false image of the Church.