I'm worried about 'streaming services as sole means of consumption of media' for a lot of reasons, but I just recently realised what exactly that means for minors.
Like, they can't legally enter a contract with a streaming service and they probably won't have a card to pay for it anyway. So (I'm guessing) most kids are stuck using the family account for whatever services their parents have chosen.
Which means that they probably don't get an opinion on what services are available to them. If they want to watch a show that's only on Amazon or Disney but parents are only willing to pay for Netflix, they're shit out of luck.
It also means kids will self-censor what they choose to watch, if their parents can check their history at any time. The fear of potentially being monitored at any time would have discouraged me from watching shows I wanted to - and I'm not even talking about age inappropriate shows (like a ten year old watching something rated R) or something that goes against a strict upbringing (like queer topics in a conservative family). Just shows that my family would see as 'weird' (anime, art films, anything remotely abstract) or 'childish' (cartoons) or perhaps even documentaries about topics I found interesting that they might become concerned about (like mental health).
When I was under 18, I always had the option of buying films/TV shows with my own money on physical media, or if a friend had it I could borrow it (we were also pretty good at internet piracy, as generations go...) so I could pretty privately source anything I wanted to watch (though I did have to do my fair share of sneaking around to watch anything on terrestrial TV). And it wasn't even that I wanted to watch anything all that controversial or shocking - I just wanted some privacy over the things I enjoyed and the safety to try something - even if it turned out to be hot garbage - without having to defend my choices to anyone else.
And I think there's probably a point here about purity culture - if you're used to having to defend your media consumption to an authority figure, you learn to make only the pure, unproblematic choices to make them easier to defend. Or you get good at preempting the argument and lead with 'yes, I know this has problems in it, but...' And when you see other people enjoying the 'icky' media, you fall into that role of making them justify themselves to you, because that's become normalised to you.
(Could this partly explain the success of Twitch/Youtube/TikTok, etc? A free entertainment source with no easy 'monitoring' of what has been watched?)