At least Facebook generally lets you review the images without having to join (not always I grant you) and only needs you to join if you want to comment on the site.
Twitter on the other hand
Not wanting to be controversial or political but what with Twitter now seemingly being the hub of woke/cancel culture, wouldn't touch with a ten foot barge pole/avoid like the plague are terms that come to mind.
Again, shame as the genuine members who want to share something non-political and of real interest are tarred with the same brush.