here is how you do it properly
https://yewtu.be/watch?v=zAT4YzVoAqU
you mount the buttons sideways, press them by pushing a lever around and get proper feedback when changing directions, especially from axial to diagonal. I'm pretty sure I had a tiny knob version of this on a flight stick, much smaller than most dpads.
Laying them flat is cheaper? Sure, but then stop gluing them together and pretending you made a stick.
wow these bozos were quick to cash in on MY IDEA
https://battlebeavercustoms.com/products/ps4-d-buttons
who would by that though, are PS4 dpads made of adamantium or something?