Is it just me or do people seem all too eager to either discount the mantis or ascribe it super-powers and malevolence?
Can a full-grown smasher break an acrylic tank? Sure, with time and inclination. I'm not sure where it would get the inclination though. These guys have one of the fastest and strongest strikes in the animal kingdom because it's designed to crack open thick calcium carbonate shells and tough exoskeletons. They are also smart enough to get compared to octopi in intelligence so they can tell that the side of a tank isn't food. The only reason I can think of them hitting it is that they want to build a burrow in it. However, since it wouldn't give much at all in the first hit, I'd guess that they'd try some other spot rather than keep banging away to see what happens. A screen, on the other hand, I can see them obliterating just because it's a blockage.
Now, can a baby smasher break a tank? Probably not. An adult can certainly smash glass and could take apart acrylic if the whim especially took it. However, it is pretty unlikely to do so, especially if raised in the tank. If it tried to smash the glass as a baby and couldn't, it seems like it wouldn't bother afterwords. Mantises have been shown to have fairly long term memory, so I suspect it could remember that the side doesn't do anything useful if you hit it.