A link alone on its line becomes a rich embed. A link inside a sentence, like the Leaflet homepage, stays a normal link.
A Bluesky post
https://bsky.app/profile/leaflet.pub/post/3mzy3t22ggc2b
A video
Obsidian's own syntax for videos is supported:
Link cards
https://standard.site
https://atproto.com
An iframe
A remote image
Images from the web are downloaded and uploaded to your PDS when Upload remote images is enabled: