I'm a younger person (in my 20s), and I think the definition of hobby is the issue when dealing with older folks. My parents also tried to get me involved in conventional hobbies like sports, dance, yoga, and crafts. While some of those I enjoyed eventually (like crafts) or not (like sports), I did eventually discover a hobby that is my true passion: fandom.
Specifically, I got really involved in reading stories about my favorite fictional characters. At first it was cringy stuff, but I got to liking more mature stories about friendship and social issues. I also went from consuming stories to analyzing them, helping people edit, to writing my own. The community helped me learn a lot of the writing skills that school didn't teach us. It also led me toward programming to make beautiful webpages, which is on my resume now. Other people like to do fanart, make fan critic videos, run blogs, or design costumes, and even eventually start selling their work.
However, the one constant for most of us is that we don't talk about fandom, especially at a younger age. Its something people will make fun of, often by older adults. And because fandom leans heavily LGBTQA+, it also is a safe space for closeted kids or those who are questioning, further leading them to hide this side of their lives.
So to our families, this all looks like we never want to get off the screen and do something, even at my age. But its a passion, community, and lifeline for vulnerable kids who get picked on by peers and adults. Plenty of older people stay in fandom, although adults tend to get less involved when real life lets us find people like us (and even marry them and read kids fanfiction bedtime stories*). In contrast, most people I know quit their childhood hobbies like sports, music, and painting in favor of scrolling through instagram.
Maybe your daughter isn't in fandom. She could be involved with rpg games, where people write one original character of a story alongside others. Or reading manga, or making memes, or programming, or any number of other great hobbies that are not mindless consumption.
I would suggest asking non-judgementally about what she does on the computer instead of assuming its worthless. Could it be? Sure. But it could be she has a real passion, and like my family, yours will never know if you pre-judge.
*CBS actually interviewed the authors of this famous fanfiction. Their fans have gotten so old, now they read their own kids this story alongside the actual Harry Potter books. https://youtu.be/1GoBTzVfn0I
Also, one of the founders of my favorite fanfiction site became a published author of original fiction. https://en.wikipedia.org/wiki/Naomi_Novik