That does sound pretty jank for other reasons but those post jacks being installed long term are incredibly common around here, and yeah they’re only supposed to be for temporary use. I’m more surprised when I walk into a house that doesn’t have them. My house has them and if you look at the floor joists I’d be scared what would happen if you spun them down haha, the joists are all bent and there’s a slight warp in the floor in the portion that don’t have them. It’s a 135 year old home so I’m not really worried about it.