I can see this from both ways really. I wouldn't want to be paying for an online class when really, you could just search youtube and get something similar for free. On the other hand, shes trying to keep her business alive and if everyone just cancels, theres a chance she might not be able to start up again when the end of this is in sight.
DHs gym have done something similar to this, they are closed obviously, but sent emails basically explaining that they are chance to have to stay shut forever if everyone cancels membership, so could those who can afford to please consider keeping paying their membership (or setting up a reduced rate), and using the online classes that will be posted. In fairness, the online ones are being posted even for those who have to cancel too, its not exclusive to those who can afford to keep paying for something they do not use, so thats nice in a way. But a lot of those who could afford to pay..wont as they can get the videos for free, so not sure if thats counterproductive or not!
Awful time for everyone really. All so uncertain..
I would keep paying if I could in your situation. I might be a bit pissed off, but if I planned on using the same person when this is over, I would try. IF it was skinting me though, I would have no issues stopping it. Depends entirely on circumstance. I don't think its cheeky for her to ask, I think its sensible really.