The stack for different architectures may go different ways, and it is decided by the ABI of that architecture. Have a look at this link
If you are referring specifically to MIPS or x86, then yes, the stack pointer does go from higher to lower addresses. (And it follows LIFO, so whatever comes at the last is removed first).
It does not matter if its from top to bottom or vice-versa (looking at an inverted stack or non inverted stack), what matters is the stack goes from an address with a higher value to an address of a lower value (as in the link you provided)