> If everyone would stop mining gold today, gold would retain value (or perhaps even go up in value). On the flipside, if we turned off all bitcoin miners today, bitcoin would go to zero instantly (as its worthless without continuous resources being pumped into it).

"Mining" in bitcoin means two different things, creating new coins AND adding transactions to the ledger. If mining reward went to 0 (which will actually happen someday), and new coins stopped being created, miners would still be able get a profit from transaction fees, although it wouldn't be "mining" in the same sense as gold.