How did race cars stop before disc brakes were available?
A better thought is: since disc brakes were made legal 5 years ago, how many teams remained on rim brakes? the answer is almost none.
And this doesn't get into things that matter for normal riding like the fact your rims don't need replacing from wear, they aren't impacted by wet weather, the better modulation, etc.
There is no real difference with a skilled operator but proponents of "the better gear" will tell you otherwise, forgetting that their main problem is in fact their lack of skill.
In the end disc brakes bikes are everywhere for the same reason 2 tons SUV are everywhere. It does not have much to do with real needs or actual real-world performance with skilled operators, sadly...
A better thought is: since disc brakes were made legal 5 years ago, how many teams remained on rim brakes? the answer is almost none.
And this doesn't get into things that matter for normal riding like the fact your rims don't need replacing from wear, they aren't impacted by wet weather, the better modulation, etc.