The feature was added in order to allow higher level users to relocate questions to appropriate categories. It was immediately abused by many, and no amount of complaining about the abuse caused Yahoo to make any changes, nor Verizon Media.
At one time, it was possible to contact the YA Team directly and report question moving abuse. If they investigated and found a problem, they were known to drop the Level 7 user down to Level 6 (not a serious repercussion, but it was something). Since the sale to Verizon, there's been no direct contact to reach out to for this particular problem, so it is rampant and no matter how many OPs and responsible Level 7s return questions where they belong, the abusers continue to move questions to inappropriate subcategories because they can. It's a strong indication of the maturity level of those users.