I have bad eyesight and wore very thick glasses as a child and teenager. I didn't start wearing contact lenses until I was 16 and my eyes had stopped deteriorating enough to make it feasible, so I had to learn all my elements either with my glasses secured by an elastic around the back of my head or completely without them. As pretty much all I could see at that stage was light, dark and strong colour, it was quite terrifying for me to skate my programs without them and my coach had to ask the other skaters if they'd mind just letting me have the ice to myself for one run through per session. Thankfully, nobody seemed to mind! They'd all witnessed my glasses flying off in spins and double jumps so probably felt it was safer for everybody to go with it.
These days, I often wear my specs (bifocal) for artistic inline skating in a sports hall (Covid permitting) and occasionally outdoors on my wheels, too. I always wear contacts on ice, though, as I love to spin and my spins are fast.

One of the good things about getting older is that my eye sight improved with age, and I no longer have a ridiculously strong prescription or even enough astigmatism to warrant toric lenses now. I do, however, have to wear glasses for both distance and reading, so bifocals are the current solution. Contacts lenses are plain, as I don't feel the vision in varifocals is good enough in any situation.
I never, ever thought I'd see the day when I was happy to wear my specs all the time, as back in my childhood wearing glasses was considered social death (children are so cruel) but I'm delighted to see that times have changed a lot since then. I'm pretty certain that the ISU would have trouble introducing a "Thou Shalt Not Wear Glasses in Competition" rule as they'd fall foul of a lot of disability discrimination policies. And I would hope that anybody who is more comfortable in specs would be able to find a way to wear them in competition if they would prefer to.