If I believe my religion to be correct, then I must believe that other religions are incorrect. If religions can be incorrect, then my religion can also be one of the incorrect ones.
I will never fault anyone for their beliefs about a god, because then I must be faulted as well. Though god ≠ religion, and I am not a fan of some religious practices.
Believing that my religion could be incorrect does not affect my ability to practice my religion or believe in its teachings.
(Remember, no judgement lol)
Winners and losers, so you are right, winning and losing definitely exists.
Wearing only a speedo and a cape with a parrot on your shoulder as you prance and skip around would be considered abnormal at wallstreet for example. Wearing a suit and a tie at a westcoast startup company would be abnormal for the same reasons as would shorts and flipflops at a bank's board meeting.
I think people mean "normal is subjective" when they say "normal doesn't exist". Still, you can objectively measure standard deviation to measure normal perhaps the right term is relative instead of subjective?