And emphasize the idea that nothing is really free . . . there's a price-paid, which may be advertiser-linked monetization, malware, etc.
My parents were extremely transparent (ha!), and really began open-discussion about sexuality/existence/basic ontology from a very early age . . . by the time I was ~8y, I had a rather decent understanding of why we humans are here, how we got here, and where we might go.
I can't say that I really understood the difference between Meiosis I and Meiosis II, but IIRC, "haploid" came-up in a few conversations.
That being said, let me tell you a Story:
I work in a PRTF (Psychiatric Residential Treatment Facility) as a HS Teacher. Technology is Integrated, and all the kiddos have laptops available for use.
When I receive a new Admit to our Facility, I have them read/sign an 'Acceptable Computer Use' form.
This is a Baseline agreement that I use to navigate the all the "Ohhhh!" moments that inevitably arise. They are teenagers, little-humans, and constantly faced with triggers and urges.
There is no escape from such things.
Our School System has innumerable firewalls, block-lists, filters, and (maybe?) hundreds of other mitigations employed.
Inevitably (and quite often), my kiddos find ways to circumvent said mitigations.
It's just human nature to be human. There is no stopping such a thing.
What I do is to remind them of a) how much of a privilege it is to be able to use such technology, and b) seek increased mindfulness in one's desires.
There's absolutely nothing you can do to ultimately stop John or Jenny's urge to seek surcease from the truly overwhelming desire to feel the things that they feel.
Our Little People are basically reproductive robots without high-level programming.
All you can do is guide, channel and re-program.
Cloudflare has an established 'Families' "Malware and Adult Content" DNS filtering system:
Malware and Adult Content
Primary DNS: 1.1.1.3
Secondary DNS: 1.0.0.3
I have (personally) never used this, yet it might help to establish a meta-layer of contravention that buys you some time to adequately discuss these things.
Apple has these strategies in-place, but they can never be end-all solutions