This is a creative way to construct a walled garden. Technically you’re allowing sideloading, but you discourage users from wanting to do this because many apps are not compatible with sideloading by promoting a feature that breaks the capability to do so.
It’s another way to force people into your ecosystem and prevent competition with an argument in hand as to why you’re not directly responsible for the effect. Clearly, monopolistic behavior.
It also seems like a really dumb strategy because do you really want to become a worse iOS? If you just decide that’s what you want, now you’re competing with Apple on their own playing field and there you will lose.