Survival is not the point, change adaptation, new ideas. Most of the time the creativity dies.
Survival is a challenge by itself. The game doesn't account for leadership change, and VE almost died due to game mechanics when the founder left. We are now locked with most elder positions forever locked out, too, highest occupied elder rank being the 7th right now I think.
If religions (and guilds) weren't so crippled when their founders left, then others would be more willing to contribute to such faiths that otherwise appear as at least partial dead ends.
The end result is most definitely not the same. If one person creates and delivers the entire theology, then one person has contributed to it, and only that one person is invested in it. When that person leaves, it will most likely fail. This is a pattern that we have seen over and over again. If ten people make major contributions to it, then ten people are invested in it. When he "founder" leaves, it will continue, carried on by the other people that are invested in it. That's what happened in SA when Mathurin left, and we didn't know if he would ever be back. Most of us thought he was gone for good. Other people that were invested in it took over, and kept things going, adding more to the theology.
You don't have to have 100% participation and activity to keep things alive. You just need a large enough core group of people that are actively invested in it, that it can survive the loss of a single key person. But as those key people leave, those that are left have to make an effort to get more people involved. That was the reason behind the large pool of elders we designed for SA, with regular elections for some of the elder positions. Keep interest going for a larger pool of noble, as well as leave the option open for almost anyone to actually become a guiding member of the faith.
It is the same, you just wrongly associated swiss cheese religions being determined only by the founder, while suggesting that those with more holes than content are the opposite. That is a bad logical fallacy. They are not tied to each other, as you can just as easily have faiths with a lot of predetermined lore that have faithful participate in order to add significant amounts of lore and theology as you can have faiths with more blanks than content never have the faithful have a say in anything. A leader guiding theology doesn't mean that he's doing it all himself and that subordinates cannot participate. A good chunk of mythology in the Blood Cult was written or inspired by the faithful, another good chunk was derived from other faiths. Every now and then, established faith with decent amounts of content will have people contribute to them (old religions with content get more of this than old religions without any, I would say).
To repeat myself: amount of content and amount of participation are not dependent on each other. Experience shows all combinations are possible, leadership style has more impact than amount of content on the short to long term, and lots of content can be beneficial on the very long term (why bother writing lore on a religion if no one cared to do so for many years prior?).
