It's very funny to me, because I spent years as a wee thing wondering how people were ever surprised to be pregnant. Yes, I know. I have studied more and learned more. But I mention this to say, if any of this is news to you, hi! It's cool. Learning is a lifelong process.
1. People who cannot conceive can have sex. Okay, remember when I said 7 reasons, it's really just one. But it's a biggie.
2. Now you might be thinking, oh you mean like queer people? And yes, them too. And before you try to tell me why they shouldn't, I'm going to note, that if you are trying to argue our bodies, and more specifically our genitals were designed for this one thing, well, then they shouldn't work this way. And they do. It's almost like some humans just enjoy giving each other pleasure.
3. People who are fundamentally, congenitally unable to conceive, can and often do, have sex. Not all species work this way.
4. People who have had their reproductive parts removed often still want and/or crave sex.
4. Some people don't want or crave sex ever, even when they are able to procreate.
5. People who have aged out of procreation, often still want and/or crave sex.
7. It's probably worth noting, that I am not trying to argue that all human bodies are inherently perfect. I personally would like to submit my knee and my sinuses for a recall. The point I am actually trying to make is that there are an infinite number of humans who like and desire an infinite number of things. Every time we attempt to squish humans into a small number of types, we both harm people and leave them out. Any policy that tries to do more of that is by design biologically wrong and intentionally harmful.
