Despite rumours to the contrary, neither the EU, nor the UK, nor any of the countries making up the EU, nor (most) other countries make up regulations for the fun of it. They are always about balancing interests of the various parties. For example some of the earliest food regulations in the US were about stopping businesses adulterating flour.

There is only one potential set of regulations that it might be in the interests of both UK citizens and UK businesses to scrap, and they are ones put in place to protect EU special interests. One talked about at the time of the referendum was, if I remember rightly, regulations about competing with olive oil producers in Greece. Scrapping any other type of regulation is very likely to be against the interests of UK citizens.