Currently in LR for iPadOS, you can only see the photos in a single album at a time. In both LRC and LR Desktop, when you click on a parent folder, you see all of the photos that are in all of the sub folders. For example, in LRC here are 2 examples of my folder hierarchy: Mtn Biking>Washington>Galby> Day. Mtn Biking>Canada>Whistler>Day. If I click on Mtn Biking, I see all of my Mtn biking photos. If I click on Washington, I see all of my Mtn biking photos from Washington. If I click on Whistler, I see all of my photos from just Whistler and so on.
In LR for iPadOS, this doesn't work. I have to drill down to each specific album to see any photos and I can see only those photos. A lot times I want to look through photos of more than just one album at a time. Like in my examples, sometimes I want to see all of the photos I took at Whistler or Galby for example. This is one of the biggest annoyances I have with LR for the iPadOS.