Because some people struggle with self-control. Uninstalling apps is reversal by installing them again.
I forget the names now as I have better control and habits but there are several apps that will block you from using apps you set a time for. For instance if I don’t want to use Voyager for Lemmy during certain hours then it would just not let me.
There are ones where you can remove them all from your iOS screen and just have borrowing text links to vital apps like Email, Messages, Phone, etc.