The idea that they should pretend to be an ordinary engineer is strange to me.
Personal itches? The idea was, their solution was objectively better. Not a personal itch. Defensible as better for the product. Just trickier to explain or support.
You reprimand a senior engineer, you'll have no senior engineers. Just a job shop with a pile of undesigned code, boilerplate from the example book that is even more fragile, unscalable, a hundred other problems that have technical debt of their own.
Code is a sophisticated topic. To blame folks who get that and can work with it, is misplaced criticism.