Some allosexual people don’t have sex, and some asexual people do have sex. But being allosexual and being sexually active are two different things. “Sexual” could imply that someone is sexually active.
Calling someone “sexual” could imply that you see someone as a sex object or otherwise sexualize the person. For example, when discussing allosexuality, we’d have to use “sexuality,” a word commonly used to mean something related but different. The words “sexual” and “sexuality” already mean something confusing. People campaigned against the use of “sexual” to describe people who aren’t asexual for the following reasons:
What’s the difference between allosexual and sexual?
It's pretty harmless to refer to someone else as shawty without their knowledge of it (unless you're speaking ill of them or trying to spread rumors), so feel free to gush about that new crush you saw in real life or online.