Your examples don't really discount rules. The person designing a collected pine from the mountain is using his visual "rules" to do so. In creating "rules," Those collectors simply recorded what they were looking at and why it appealed to them. BTW, no one really wrote any of this down. It was accumulated knowledge of what works effectively.
FWIW Willie Nelson (God and Texas love him), is a natural musician. I have a friend who is one of those people who can sit down at a piano or pick up a guitar and play instinctively and very very well. It's an astounding talent, but there are folks without that innate ability that can become equally good with the right instructions and understanding the rules of music.
Willie plays most anything and is proficient in a number of musical genres from country, jazz, blues, folk, rock and Latin styles. I was listening to him when he wore a button down shirt and tie and had short hair in the 60's. I Was a teenager when he helped create outlaw. HOWEVER, ALL those styles involve "rules" of music--which is about as "rules oriented" as you can get. Music is fueled by mathematics. People pick up on that, and use it (Bach for instance) Mathematical progressions in chords, scales, intervals, patterns, tone and pitch are all "rules" musicians play by. Just because some innately understands those rules doesn't make them unnecessary. They come with the territory. Where others may need to refer to sheet music, some musicians play by ear. Doesn't change the rules of the notes they're playing. They can riff on some things, improvise, but such efforts still have to hang together with the basics. They know how to put all those pieces and rules together innately, in some cases. In some cases, they're learned. Both paths can lead to good musicians, or to really bad musicians. Bad musicians come in both categories.
With bonsai, some people have better sense for where things need to go in a design. Others need a path to follow. and BTW, some folks who think they have that innate design sense often really don't and their trees show it. Also BTW, THERE IS NO SHAME in using a template to create a decent bonsai. Assuming those that leverage rules are somehow lesser than someone who bitches about them is not only silly, it's not true. I think Americans get REALLY caught up in the "I am wild and free and nothing can constrain me," "if you don't do it yourself it's not authentic," way of looking at things.
All that is simply not true and a bit blind. The "I do it MY way. I do it MYSELF because I'm special and have innate artistic talent" attitude has held American bonsai back for years. It was looked down on for decades if you "bought" a tree--in any stage (and still is by some who don't know what they're talking about) instead of making one from scratch...That lead to a LOT of self-created crap and mediocre trees. Still does...