Go for it! Get a motherboard with reinforced PCIe slots for both GPUs though, the cheaper mobos only have one armoured slot. Also, you really should use the 3080 Founders Edition I guess for a dual setup as they blow out part of their heat in the back. Otherwise you need good air control and as thin 3080 cards as you can find (so there's some space between them in the case). Still waiting for good thermal benchmarks on this kind of setup...
Of course if money is an issue, you are well off with only a single 3080 :)
There is no point in buying the 20xx series anymore. The 30xx are twice as good for the same money (if you can get one).
Woah, there. They said they were just learning. No need to purchase special hardware until you're trying to run state of the art models.
You can get very far on any laptop before hardware becomes the main blocker. And before building an ML machine, there are cloud compute options available for far cheaper.
Of course if money is an issue, you are well off with only a single 3080 :)
There is no point in buying the 20xx series anymore. The 30xx are twice as good for the same money (if you can get one).