I have literally thought about this for years. As a lover of links golf, I prefer courses based on the original way the game was played.
That said, I try to be somewhat open minded.
For instance, my home course has a short par 5 that meanders to the right. There is a wall of trees on the right side that is a legitimate defense against shots hit right.
On the same course, there are some trees that overhang another fairway and block the view to the green from the same fairway. Either the trees or the culprit limbs should be removed IMO.
I don't want to take this thread in the wrong direction, but to me it's about defending the hole, mainly by measuring scoring average. I believe if you remove one hazard, you can add another or maintain the hole is such a way that scoring is unchanged. If you remove the trees, you can add a bunker and make it shallow or deep or narrow or wide. You can tighten the fairway with rough. You can grow the rough. You can quicken the green. It's possible the trees are a really good defense or are really pretty and make the hole look good.