> I'm still using the magic mouse because I found click-drag with the trackpad to be shitty. Is there a trick to that?

Not sure how the magic mouse works, but there's "drag hold" on the trackpad. You "double tap and hold". Tap once, and on the second tap you don't lift your finger off the trackpad, but start moving it around.

Conveniently located outside the trackpad settings, in Settings -> Accessibility -> Pointer control -> Trackpad options -> Enable dragging. https://imgur.com/a/oSrPyDB

You may have to activate tapping (as opposed to pressing the trackpad).

"Without drag lock" actually does lock, but only for a short time. "With" locks until you click again. "Three finger" is new to me, never tried it.

edit: screenshot