Also, please don't add editorializing headlines adding a clickbait framing. (California isn't "banning high end desktop computers", California is requiring them to have efficient sleep/idle modes, and Dell hasn't implemented that for all their models)
The page states "California, Colorado, Hawaii, Oregon, Vermont or Washington", why the focus on California? Is this a recent law for California while the other states have had it for some time or something?
The headline might be a tad clickbaity in its selectiveness. However, you can make pretty strong argument that California stands out from the others on that list. Because California is (for the moment) the worldwide epicenter of computer technology. While none of those other states have much of a meaningful tech industry.
They don't. If a powerful server is poorly-designed and doesn't sufficiently reduce its power consumption when it idles (as this computer fails to do), then it doesn't meet regulation, but generally powerful servers are designed more professionally than consumer-grade Alienware gamer computers, so I wouldn't worry about it. You fell for clickbait.
Even better, there's a general exception for well-designed computers that have efficient idle/wake cycles (which includes any computer being used in industry, gaming PCs just tend not to be terribly well-designed), and it's not new.
So no, nobody "just" did anything and nobody is prevented from doing anything other than importing poorly-made Alienware computers into five or six states that are interested in mandating a level of responsibility on the part of computer companies. The entire issue here is that Dell just hasn't bothered making this computer in particular have power usage while idle fall under a well-understood guideline that exists in 10% of US states. It's entirely clickbait.
The more I read about California (and to some extent other extreme-left states like Oregon), the more it truly does seem insane. I used to be put off by California just because of the weather (good weather to me means heavy winters and cold year-round). Now I'm fully confused why people still want to move there when the leadership and policies are absurd, traffic is hellish, cost of living is towering, and even day to day life is impacted by drugs, crime, and natural disasters.
This PC only has a a 550 Watt PSU. For context, NVIDIA recommends a PSU capable of delivering at least 750 Watts for an RTX 3080.
Is this one just not efficient enough? I don't see any 80+ badges, but it's a pre-built so I wouldn't necesarily expect something like that to be front-and-center in their marketing material.
EDIT: Other comments say this is about power draw when idle. That makes sense.
Your PSU has an efficiency curve. Chances are that you use more power with your 550 watt PSU compared to a 750 watt one, since it has a lower efficiency while supplying the needed power.
I don't know how efficiency curves for modern PSU look like, maybe it isn't too relevant. I think most PC are well served with their optimal efficacy at around 300W.
Here is a curve, but I don't know if that is representative of reality:
Also, please don't add editorializing headlines adding a clickbait framing. (California isn't "banning high end desktop computers", California is requiring them to have efficient sleep/idle modes, and Dell hasn't implemented that for all their models)