People complaining about the price/performance of the new Mac Pro, as always, since the first PowerMacs ever built, have no idea what they're talking about and should be ignored completely without even a second's worth of thought.
Anyone who knows what the components inside this machine cost, as well as what it costs to design, engineer, R&D and then assemble a machine like this in the US knows that about the only thing "overpriced" about it is the RAM, although, as it must be pointed out, not nearly to the extent to which HPE or Dell juices their professional customers. And, as always, you're free to buy your own.
As an interesting aside, no one seems to truly know the price of the Radeon Instinct MI60 (which is essentially what the Vega II is) - however, the MI50, which was the slightly down-clocked, 16gb version of this card is "known" to list at ~$5,000 for enterprise buyers. And even at that price, I have seen multiple people with more knowledge than myself indicate that they are still likely losing money on these cards at that price. So. Think about that before complaining about the price of the GPU upgrade.
I do think the RX580X as an entry point is a bit poor, but then again, if the buyer is bringing their own GPUs, then they likely won't want anything better from Apple anyway. Plenty of people out there with their own Radeon VIIs or 5700s that they'd like to drop in. I'm certain that the 580 isn't the main driver behind the $5,999 MSRP anyway.
I also think it ought to come with 512gb of SSD standard, and I'm assuming it will within the year, but again, we're nitpicking. Any claiming that this machine is "ridiculously overpriced" is boldly exposing their utter & complete lack of knowledge about anything related to this topic. And I think, at this point, we can hit the mute button on all of them.