The difference between many systems and one system give an honest Protestant options to leave, for example, when conscience dictates that the pastor is out of line with Scripture
The contrapositive is not true - that an honest Catholic hasn’t the option. The majority of priests are in line with doctrine. A few do step out of line and most are called on it either by visiting clergy or by a Catholic in the congregation who is knowledgeable about the faith.
Also bear in mind that a bad pastor is not the same as bad teaching across the entire church. If a Presbyterian minister is out of line with his teaching, the congregation can, with minimal difficulty, attend a different PCA chuch. Likewise, there is fluidity with which parish Catholics attend. There’s not
supposed to be, but often Catholics will attend a parish that better fits their needs at the time, for example a young family would commonly choose a parish with a school and programs for kids rather than the ‘assigned’ parish which has mostly elderly parishoners. I have heard of Catholics leaving a congregation because of a bad priest - mostly because he’s abrasive rather than being out of line with doctrine.
The Pope serves for life regardless, I don’t suppose any human or humans oversee him.
I think too much is made of what the Pope
could do as opposed to what he actually does. It is rare for a Pope to do or say something without the support of the College of Cardinals, a body of the most senior, educated and experienced clergy, from which the Pope is chosen. I can only think of one example in church history (dating back 500 years) when the Pope exhorted doctrine over the objections of the Cardinals. No, the Papacy tends to be a very conservative office, and if we had a Pope declare something absurd or heretical (such as “Jesus never actually existed”) we’d see some form of action taken to remove him from power. That may not be on the books, but the Cardinals are educated men who understand that the Magisterium must not deviate from orthodox doctrine except after exhaustive deliberation (as when the doctrine of limbo was called into question a few years ago).
The major difference between say one Protestant church (Baptist) and the Catholic church is the difference between heterogeneous and homogeneous.
Back to your valid concern.
What happens if a practicing Catholic has qualms with what the priest is teaching? The priest is responsible to the pastor of the parish (an elder priest) as well as to the bishop or head of his order. If it’s an issue with something other than theological matters, the parish council or board - composed of elected lay persons - often has overriding authority. For example, we locally have a very liberal priest who, while he’s very focused on living an active faith, crosses the line with his homilies. Three consecutive Sundays he exhorted and praised the gay community for their courage. He was censured - reprimanded following a meeting with the Archbishop who cautioned him to stick to orthodox teaching. Yes, there is room for homosexuals in the Church as there is room for all sinners. No, that should not be the focus of multiple homilies, and should certainly not be subject to praise. So there is recourse.
In practice, the process of Mt 18 tends to be performed by the clergy or some parish or diocesan leader during either a regular business meeting or a special council with relevant persons. I’ve heard of evangelical churches challenging a pastor directly during services - this would be considered disruptive in the Mass. And while lay people are free to voice their concerns to their pastor, not many Catholics know their priests and their Scripture well enough to do so. Those who are disenchanted - whether rightly or wrongly - tend to just leave or at least stop going.
If I was stuck with a pastor like Phelps,
May such a happenstance never befall you.
I could cite said Scripture, and in many churches, there is a procedure to discipline or remove an unrepentant embezzling or womanizing pastor.
Embezzlement and adultery are bright-line issues about which there should be no contention, and the process of calling such a pastor on the carpet as in Mt 18 should be a formality. What about theological dispute? The difficulty in carrying out Mt 18 is who ultimately decides who is right? If 300 of your 500 parishoners side against you, do you acquiesce to the majority, take the other 200 and start your own church, or do you kick them out and claim rightful leadership of the church property - since churches are often non-profit corporations that own their own buildings and land?
One benefit of an organized denomination is the ability to appeal to higher human authorities when a conflict at the local church becomes unmanageable. Not that this always prevents a fracture (consider the recent split among American Presbyterians), but it allows cooler heads to come in and attempt to settle the dispute.
If nothing else, a mature Christian who is discerning can leave. We lost Christians because we had a female (and otherwise disciplined) pastor for some time, and they could not abide by Scriptural requirements for a woman not to lead a man.
One would hope that the cause of discernment would lead one to take a leadership role in the church. I’m sorry to hear about the fracture yours suffered, and I hope you’ve not lost friendships as a result. I don’t think any church is immune to it, only that each approaches the threat of schism differently according to its organization.