If I read this correctly, they’re “bypassing ASLR” because the binary isn’t PIE, so it’s loaded at a static address.

I would not consider this actually bypassing ASLR, because ASLR is already turned off for a critically important block of code. Practically any large-enough binary has gadgets that can be useful for ROP exploitation, even if chaining them together is somewhat painful. For ASLR to be a reasonably effective mitigation, every memory region needs to be randomized.