I took piano lessons from an early age up until I graduated high school. I didn't like to practice either.
I wish I had my lovely Petroff piano again. A lot of the songs my sisters and I used to play on the piano just can't be done on an electric keyboard. Not enough keys.
But. I have also come to the conclusion that some areas just aren't a good match. I help at karate class, and I see the kids whose parents want them in this, but the kid has not interest and therefore doesn't put in an effort. Maybe it just isn't a good match. Maybe the kid's talent lies elsewhere. I agree it's good to try things out to at least find out. But to push it when their heart isn't in it...I'm not real sure about it. It can be a good therapy when you're having a bad hair day, to sit down and pound the keys.
I also played flute from 4th or 5th grade till I graduated high school. We had practice cards, so we pretty much had to practice to make some of our grade. I didn't like that any more than practicing piano, but I did it. I also, having been exposed to all other sorts of music growing up, would try playing a lot by ear. If I heard a song on a record, I'd try playing that by ear.
I will say that even with all that practice, loving the songs played in high school band (I have 95% of them on CD), I never achieved the vibrato I would've liked to have. Nor the finger speed. But I stuck with it.
Tough call to make, K.. 11 years old is on the brink of teen years, which brings a lot of finding her own way and thinking for herself and that brings a lot of head butting between parent and child. You could compromise with her. Suggest, perhaps, that if she wants to drop piano, then replace it with something else. Maybe a gymnastic sport is more to her liking. Or martial arts. Maybe some other instrument. If she can't come up with a fair compromise, then stay with it until she can. She could be very helpful on the piano with kids at school. If she became proficient enough, kids in band compete in solo/ensemble competitions. Soloists often need an accompanyist. She could consider that.