Most companies do both. If just asking users questions was strictly better than passive tracking, that's probably all they'd do - analytics have a real cost to use, that cost wouldn't be paid if the information gathered was useless.

But, people are pretty remarkably bad at asking for things. It's mostly the "better horse" problem. People ask for fixes to proximal issues (make this faster, cheaper, better) and not the big things.

In my own product, we use gtm to understand where in our sign up funnel people fall off. It is a complicated product and a complicated sign up flow. Since people who fall out of the funnel are unreachable, we can't just ask them why. But we can observe that (say) 40% of users bounce off of step X, so let's make that step easier.