I don't like it because of the outrageous amount of energy used to keep all that ice frozen, and all the fish inside frozen enough not to decompose, since people are walking in and out of that room all day. Especially when it's so much easier to get plastic models or even to preserve dead animals in their natural state inside blocks of plastic. They are more visible inside blocks of plastic, you can position them so that people can walk around them and view them from all angles, no coats necessary and no ridiculous wasting of power.
Personally I think a display of living animals is always more interesting than a display of dead animals, and we're fortunate enough that the vast majority of fish can be displayed alive without causing them suffering (this is not the case with, for example, elephants and large marine mammals which are miserable in captivity and probably should not be displayed alive.) TBH I'd be a lot more inclined to go see a public aquarium with live fish because I can then see the behavior of animals I wouldn't normally see (and some pretty fish tanks) - if I just want to see 'stills' I can see them in photos and it doesn't make that much difference, because they probably wouldn't let visitors get too close to the ice anyway.