Yeah it's... weird. I'm still unsure about it.
It's basically, "here's an ActivityPub feed for your photos, and also a portal through which to view photos on other ActivityPub feeds." The web client displays photos a little nicer than the mastodon web client, sure.
But... I'm still not sure why I want all my photos in a different silo, or why I'm now managing two different follow lists. I don't yet see the benefit... but that's also not stopping me from posting selfies. ;)