That is a huge price tag for a very simple piece of equipment. Even factoring in the R&D and low demand.
I suspect putting $200 into photography classes would pay more dividends to one's photography than an L-bracket. Something like that ought to cost $20, tops. Good grief, a few years ago, I bought a custom-designed mounting bracket for my home theater projector, including several pieces of custom-cut metal (much larger than an L-bracket), special screws, etc, designed and sold by an enthusiast for one specific projector, for about half the cost of the L-bracket.