If he wants to display them all, that defeats the whole purpose.

Uh, what? What exactly is "the purpose"? To me, it's display something interesting that also reflects my personal interests. Not so long ago there was a guy who had a wall full of Hot Wheels cars in packages. People on this subreddit said "That looks ridiculous. If you want to display cars, get one scale model car and display that." Same idea here.

You then wonder if you can touch them? WTF? You're so far beyond the purview of atheistic design and getting into how guests should behave in someone else's apartment. Completely irrelevant to this discussion.

Not at all. My only point is that the way he has them set up makes it look like a museum display. Tell me that exact arrangement wouldn't look right at home in a museum with a glass case around it and a little white card.

I would hope that guests wouldn't come in my home and start playing with my stuff, but be realistic. This is a living space. Life happens. And that includes someone putting a drink on a windowsill, or someone getting a little to hands-y with things. That has nothing to do with whether it's social acceptable. It will happen. And generally you want things to reflect that it's a living space and not some meticulously curated display that you're going to freak out over if someone touches, a la the action figures scene in 40 Year Old Virgin.

You say it looks fine. I say for a small apartment 4 cameras and accessories is overkill for an art display. It's ok that we disagree, but don't act like I'm crazy for suggesting so.

As Caleb pointed out, his house is full of art. Just not the type you apparently prefer.

Read more carefully. My criticism is the quantity, not the type. Never did I say "get rid of all the camera / film art." I said "Balance the abundance of cameras with something like a print (which can still be film related) to give the decorating and spacing more balance.

By all means, make constrictive criticism, but there is almost nothing here that throws any red flags that is worth critiquing.

I provided a criticism, along with a solution. By the very definition, that is "constructive criticism". You, on the other hand, are pretty much telling me my opinion is dumb. And no, there are no "red flags". And I even said the space and setup were "nice". But instead of of critiquing anything it seems like you would have preferred another "awesome bro" comment.