It really sucks when you try to stomp flat a dent-free standing can with a bare foot and you happen to get the angle just right so as to come straight down and the damn thing doesn’t crush. You may as well be stomping on a piece of 3 inch drill stem. Fortunately you almost never manage to get the direction & distribution of force perfect and the can usually does crumple when you imperfectly make contact.
That is something that never occurred to me to try.
That handstand was pretty impressive. Too bad the video quality sucks.
In fact, the shape does matter . It can go either way, the shape can make it weak and the shape can make it strong.
If the glass was a spiral like a spring, then the force is bending the glass, and the compression test isn’t valid, it would to be a bending test performed.
Having features like sharp corners (notches or protusions) can lead to cracking at the corner, which weakens it rapidly…
However the drinking glass , as long as it has gentle curvature (so as to be a valid arch, no sharp corners, no notches or protrusions … is strong in compression ) is even stronger than than the cube due to the skin effect. The skin of the glass is stronger than the insides of the glass, so a shape with more skin ( more perimeter with same cross sectional area CAN be stronger than the cube or or cylinder. This depends on the quality of the skin… if its been scratched or pitted, it can be weak again… ).
No matter, the bench test of the cylinder with the same cross section area as the sum of the cup’s cross surface tests glass as being very strong in compression.
However the engineering idea is that these relatively brittle materials (like glass,ceramics, concrete… ) will basically explode their insides out of subject to too much compression.
My kid did a trick where he crouched onto an empty soda can on one foot, then barely flicked two sides with his fingers and the thing collapsed impressively fast.
Don’ drink much beer out at the farm, do ya? 
Circus people are known for, even proud of, their shitty video quality.
Now, carnies on the other hand, well, you know about carnies.