I don't like the euro, but as an european citizen i have little choice but to use it directly or indirectly.
And although bitcoin will never be enforced by law, the fact that bitcoin has so many advantages will make bitcoin run in the background of many apps at least. Basically 'forcing' people to use bitcoin (even if they don't know it). Most of the time this will be indirect use of bitcoin (if people don't want to use it). But people who use bitcoin directly, without any 3rd parties will be better off. Which is why most people will likely choose to use bitcoin directly.
Choice is an illusion. Yeah we have free will, but the current society does everything it can to limit your viable options as much as possible, because it's easier to control masses of people if you limit their choices. And it's easier to profit from economy of scale if the choices are limited.