It doesn't look very seamless. If you had a Loom account, you don't automatically get a Dropbox account. You have to make a dropbox account and then link the account to "import" your photos. I guess you can put your photos into Dropbox's "Carousel" but none of this happens automatically.
I've actually just done it - it was seemless (though, as you mentioned I had a dropbox account). I clicked the link, read the page, signed in to loom and then authed loom->dropbox. Process started instantly and photos started showing up! Plus now I have 0.5T on dropbox.