The problem - and thats the reason the GDPRs try to improve the world will fail - is that if you as a company to say: "if you don't consent you cannot use this great service all your friends are using.
The people will consent even if they don't like it so you need to remove this force factor.
Its like here in germany its prohibited that you let an employee work for more than 8hrs straight. In special cases you may extend this to 10hrs but only with good reasons. Everything above is just plain illegal, even if the employee states he did it voluntarily. The company is still liable then.