We found with our eldest that we did an average of an hour a day most days over the summer holidays - some days nothing at all if we were off for a family day out, other days maybe two hours if there was a test she wanted to do.
Honestly, an hour a day average is really not that much - how much vacant screen time are children generally having? I think some people have this rosy idea of children who aren't studying playing magically in fields, capering around healthily with lambs, when in actual fact, most of them are glued to YouTube shorts or the television.
We had a list of things to do each day - something outdoors (weather dependent), some structured 11+ work, some music practice, something with her sister, something creative - and when she'd done all of that, some screen time was granted. That gave a bit of structure to the day and screen time felt like a reward or payment for work, not a default.
I don't think any of that sounds cruel - and we weren't rigid - e.g. if we had a long car journey, screen time was fine. If she wanted to have a sleepover with her friends, we didn't enforce anything etc. It worked for us.
One thing that did disgust me is one of DD's friends had her phone confiscated after she didn't qualify for the 11+ as punishment for not working hard enough. I would never have done that.