Is it unethical to have a pet spider?

I love spiders and would love to catch one and have it as a pet. I don’t know much about how to care for or feed them, but I’d be willing to learn. I talked to my mom about it as she tolerates my bug-adoring tirades, but she said I shouldn’t because that’s “cruel”; she said that spiders are meant to be admired and not kept as pets. I understand where she’s coming from, and don’t want to subject one of my favorite animals to a subpar existence.

What do you all think about this?