I routinely need to do this using interfaces that aren't driven by a mouse. On my phone, for instance, where despite having inertial scrolling, it's strain inducing to repeatedly flick through pages with large quantities of content.

I’m assuming you use Android.

On iOS the scrollbar is only invisible when you aren’t scrolling.

Whether it’s visible or not, you can drag it with directly with your finger just like dragging desktop scrollbar. No need to induce any strain.

The same is true on the Mac.

This entire issue is only about the default at rest behavior.

Scrollsbars are visible during scrolling, and if you want them the whole time, that’s a setting.