We had the same rule, and modified it to include type of games. Phone games have time limits, unless it's things like Dragonbox, flow free, or other "educational" games (at least games that require some kind of thinking) approved by us beforehand, including minecraft. Because 99.999% of games for children are just absolute trash stuffed full of ads.
Any PC game that is age appropriate gets a pass, but only if it's evening and we're inside already, or if it's really shitty outside.
As a non-tech person, the one thing I haven't been able to figure out is how to encourage 'tinkering' in an active way. So much technology today is meant to be set and forget. I had my oldest build a linux pc last year, and that seemed to pique his interest, but it was short lived, because so much is just apps and consumption with no backend. Even age appropriate apps for programming and learning about that sort of thing are very boxed in.