Everyone knows everything — at least everything relevant — especially those who have given things very little thought.
If you happen to be one of the few who puts serious time and effort into earnest, deep and self-critical reflection, please keep in mind that those who focus on practical matters do not see this effort as yielding much value. They see how you waste your time splitting hairs on irrelevant and esoteric topics. You call that wise? It only proves that you lack their talent for discerning what matters most. Is it really so strange that they believe they know better than you?
Every horizon is the edge of the world.