So when he crashes and burns, or dies of a drug overdose, I’m not supposed to care?

Cool. I think I can manage that.

I was told way to early on by older friends

There’s your problem.

3-4 year olds don’t need to know about birds and the bees

Why not? It’s interesting and biology is part of the natural world around us.

Some kids probably won’t care but others will be super interested. Start the conversation and see where it leads.