Do whatever you want but don’t expect the French to stick with her long-term if nobody in her family speaks it.

I'm a developmental psychologist and I think the concern about screen time is sometimes overblown for school-aged kids. We only have evidence of detriment at when it's many hours a day and that is mainly from opportunity costs (e.g., less time outside, less physical activity, less face to face social interaction). The general recommendation is not to exceed 1-2 hours a day and focus on quality of engagement during that time.
I personally think it's more important to build an attitude that screens are a tool for learning and enjoyment not a mindless habit and to teach your kids to self-regulate (e.g., monitor their time, monitor their enjoyment/learning) so using screens purposefully to improve French falls in that category. French show with French subtitles on is a great way to learn even if they are an early reader.

Anonymous wrote:I'd much rather listen to a kids show in French where the words aren't distracting, then in English where I'd comprehend and been annoyed.

But also maybe there are good French TV sbows/movies?

Strongly recommend Miraculous Ladybug. It’s originally a French show and is engaging. Being bilingual is massively good for your brain, I disagree with the notion that no TV outweighs the benefits of bilingualism…

I'd much rather listen to a kids show in French where the words aren't distracting, then in English where I'd comprehend and been annoyed.

But also maybe there are good French TV sbows/movies?

I often hear people from other countries say they learned English by watching American television. I can only imagine the reverse is helpful, too. My sister watches tv dubbed and/or with subtitles in another language and says it helps.