That people show off these illegible globs in public only makes sense from a signaling perspective: They are saying, “look at how many nodes I have in my brain, amazing nodes, I have so many nodes that a peon such as yourself can’t even guess what’s going on here!”
What percentage of history's greatest and most prolific writers did not use a Zettelkasten? More than 99%, probably. Luhmann is an exception that proves the rule.