Using caps provides emphasis when necessary and usually connotes shouting. It isn’t a bad thing to do but it is a standard protocol for forum discussions. It is just a matter of being polite and exercising a bit of etiquette. If one has a disability that makes using two hands or the shift key difficult, then typing all in caps or lower case is understandable, otherwise it is always nice to exercise good manners.:)

Aside from it being a standard internet protocol, it is also polite to respect any forum's standards of procedure and behavior. We are all essentially guests here. While I have left forums in the past that simply erked me with their expectations, I never questioned them while I was a guest there.
Just my POV.

Hi Otto, I see that this capital business bothers you. As someone who is probably old enough to be your father, let me give you some advice. Relax, take a deep breath, go with the flow. This is the way we do it here. Not using all caps is not the end of the world! After all, we are all here for the same reason, to learn and to share. All the best, Norm.