I think that depends on the individual, doesn't it? If it were me, seeing photos of people or things that I valued which no longer are... would mostly bring me sorrow, and very little joy.

[ The sentiment to his words may be sad, but if he thinks it's sad, then he's very deliberately choosing not to show it, judging by the fact that his expression doesn't change. ]

But... I agree dog photos are cute. [ ... ] Cat photos aren't bad either.

[ lowkey he may have looked at cat memes in the past and quite enjoyed them. ]