> You mean click with three fingers once and let go to initiate a drag, move the cursor with one finger on the touchpad to its destination, then click and let go with three fingers to end it?

Not quite.. on macOS, you can enable three-finger drag which means that when you touch down with 3 fingers and drag them on the trackpad, it's the equivalent of clicking-and-dragging with a mouse.

There's no laborious use three fingers then one then three again. Just like swiping with 2 fingers does scrolling, using 3 fingers just grabs whatever's under the cursor and moves it (whether that's a window, or starts selecting text, moves a scrollbar, anything).