Nostr doesn't host images, so every post thay shows an image links you to another server. If I wanted to capture a bunch of people's ip addresses I could self host an image, include that image in a post, and then capture the ip address of the people that look at it (when they query it from my server).

To add: since nostr doesn't host media, if someone posts a picture they are self hosting, they can get your ip address when you load the picture, a VPN is recommended.

No you can’t!

Hiya and welcome to the future 🫂