I've watched several guys try endlessly on ridiculous gear, like a racing high-aspect flat wing and long mast, and not get it, unsurprisingly.
For myself, starting foiling at age 62 after 12 years of kiting, the secret was a large board, short 15" mast, and simple medium aspect wing (original Slingshot Hoverglide). The unfortunate part of learning that way is that having become comfortable on that heavy old aluminum mast and wings I find it almost impossible to ride my friends' modern carbon wings. I just get tossed off them. On the other hand, a local friend managed to learn on a carbon wing and 24" mast by simply persisting endlessly, he would literally send several hours nonstop porpoising all over the place for several weeks, and two weekends ago I watched a guy at Cape Hatteras do the same. Both of them eventually smoothed it out, but that seemed like way too much effort. A short mast and large board made it much easier for me, my buddy and I were taking short flights on the first day, sustained flights the second session, and moved to 24" mast on the third session. I love riding a 36" mast now.
But yes, you feel like a complete novice to start, an unstable fawn is a great analogy, and it is very taxing. Half an hour is still about all I can handle for a session if I am working on new things, like flying gybes. And I only got the latter because I stuck with a large board that I could do touchdown gybes on and gradually advanced to turning to toeside at speed and flying. Getting back to heelside is still about 50% success, especially if I don't have enough power. But it's great not to be crashing and restarting every transition. All my friends who have mastered the flying gybe did it on short boards with endless crashes first. Now three of them are so good it is sickening, riding carbon foils with pocket boards and doing 360s etc, although none have managed to get to the foot-switch gybe, that seems really hard and I don't even aspire to it.