Not all who yell "MAGA!, MAGA!" are really MAGA.

True in any movement.

People like to be on the winning side for a variety of reasons, some philosophical and some personal. Happens in ANY movement. It's just human nature; we do, as a species, tend towards selfishness if not actively kept in check.

Every battle we win, watch who instantly drops that issue or event to effortlessly segue into finding new issues to complain/whine/obsess about. ... Is this a mere flaw in their psychological makeup? They can't celebrate all the winning because that's just not how they're wired?

Mostly, yes.

Human nature again. Some people are never happy unless they are unhappy. Some may be, as Cates suggests, enemy infiltrators trying to pull your morale down.

But most people are simply human beings, with all the flaws that entails.

Morale is important in an information war.

It is.

And being so suspicious of everyone all the time is not good for morale.