For a more serious answer:
I think we get this impression because most of the builds we see are showcased by “professionals” (or wannabe pros), the key being this:
People spotted a potentially large emerging market and are trying to position themselves.
(Not blaming, it’s a fair thing to do).
The people who just come up with an original build, min-max it, and want to share it, DO write guides. But these trees are hidden by the forest of competing Youtubers.
In adition to the 2 great ones posted by Llama.