Good demonstration of the weight shift charles. Note that in his clip before he "pulls" or strokes his arm is forming the catch. When the weight shift occurs he is already in an anchored position with his arm.
Some people won't be ale to form that good of an anchor with the forearm before rotation starts, and that's OK. What's important is not letting the "anchorage" part be rushed.
The speed of rotation doesn't need to be fast especially if your swimming pace or tempo is leisurely. The movements need to align with your forward speed.
Have you ever pushed one of these?
From a standstill or slow speed, the speed of movement of your pushing is very slow as well. You cannot rush it or you'll hurt yourself, your hands will slip off or you'll waste energy. As the rotational speed increases you can increase your movement speed as well and the timing of seeing the approaching bar, placing your hands on it and pushing it with just enough force to either keep it going or speed it up changes. At some point you may have a "steady state" speed at which you can keep your timing and movements the same and keep it going at the same speed. YOu probabaly could find several "steady state" speeds as well. But with each different speed your timing would change. you'd approach the target area faster, meet the approaching bar with some already developed forward movement in the directin it's already traveling and then push with just enough force or for just long enough to keep it going. then you could either try to maintain a faster tempo or take twice as long between pushes adn let it slow a bit and have a more liesurely tempo.
Swimming is a lot like that. There is not just one speed of hip drive.