Straightforward: my 29-year-old son is dating a 16-year-old girl he met at a jazz festival this summer. Openly. He had a same age long-term girlfriend until last year, when they broke up amicably. We really loved her, she was basically our daughter-in-law and we’re still in touch. His current girlfriend’s parents know about their relationship & are cool with it. For the record: it’s also legal in our country. We don’t think it’s right though, he’s a grown ass man while she’s a high schooler. He’s also very successful professionally, handsome, takes good care of himself, has a good personality, etc. so it’s not like he’s lacking options. He just says he likes her - that’s his why. He’s not a bad person, I know that, but still this whole situation has changed our perception of him quite a bit. We’re having a rough time to say the least.
The only reason grown ass men date children (laws on the age of consent were written by those same grown ass men, they don’t dictate reality) is so they can have someone who hasn’t yet learned how to recognise red flags to coerce and control. You don’t need to actively encourage him to be sending him the message that you, at the very least, don’t disapprove.
It’s up to you to decide how comfortable you are with sending him that message, and act accordingly.