If you're doing anything complicated, Excel just doesn't make sense anymore. it'll still the be data exchange format (at least, something more advanced than csv), but it's no longer the only frontend.
"No one uses" is no longer the insult it once was. I don't need or want to make software for every last person on the world to use. I have a very very small list of users (aka me) that I serve very well with most of the software that I generate these days outside of work.