The problem is that it also prevents countries from reducing the regulations in order to foster local innovation, avoid disadvantageous rules (there are more lobbyists than bureaucrats in Brussels, for a reason) or adapt to a new reality (AI being a good case). Moreover, each country still have their own specific laws, the EU regs come on top, and don't decrease the amount of laws. And the EU votes a lot of laws, since its the main power it has, on average 7 per day.
Individual countries are free to scrap their own regulations that are redundant or counterproductive due to EU regulations. There are still a lot of domains that are not or under-regulated by the EU. Since that doesn't seem to happen, something on the national level is not working, and the utility of national legislation over EU legislation starts to seem doubtful.
