Long Island is an area of New York. So in theory there's little in the way of regulation, but it's an island, and the local deregulated operator is also a complete monopoly... you cannot choose between power companies in any way, shape, or form.
Also, as is traditional for local enterprises, it is chummy with the highly corrupt local politicians, and as such charges astounding rates and still "loses" money every year.
If you're thinking that I am an embittered local exaggerating for dramatic effect... well, here is a screenshot showing their understanding of what the purpose of their business is (from their 2020 SEC filing):
View attachment 275228
In English: "We take huge losses so that our highly dubious personal investments don't lose money, and use that money to buy politicians to prop up the utility business that we just looted, so the taxpayers can have rates double the national average AND pay for our thievery in their tax bills. Every time this generates outrage we will shout bankruptcy and sell out to a different LLC and probably not even have to rearrange our pencil drawers, let alone move offices.")
Wow Jetsam, you and I need to sit down over a coffee for a Long Island history lesson,... I'll buy.
But that's for another thread, now the matter at hand:
You responded to a well written post from PeakBagger, but his positioning of Ronald Reagan is off by about 20 years. The push to deregulate the US electricity sector was under the final years of the Clinton administration, and the lead flag carrier was Kenny Lay, CEO of Enron, who was a hugh backer of Bush the Junior. I cringed every time I saw GW walk down the air-stairs from the Enron Boeing 737 during the election campaign.
So the theory of deregulation, and the goal of saving consumers money in their electric rates, was that all the local Utilities needed to be forced to give up their ownership in generating/power stations. Thus allowing the Generators to independently compete against each other in an Energy Market Place, thereby allowing private Energy Marketers (ie middlemen) to purchase and resell this power to consumers at lower costs. The Marketers would sign up consumers promising lower prices, and sometimes higher prices because their electricity was originating from clean green sources (wind turbines and solar farms). The local Utilities would remain fully regulated and would be the cashiers/deliverers for the Marketers, but would be acting as a basic minimal cost pass-thru. Therefore consumers could feel safe because the Generators would send the electricity directly to the Consumers via the same poles & wires as before.
Naturally the govt needed a safety net, so they designated the local Utilities as the "provider of last resort" if the Consumer didn't want to participate in the "free" market. Most Utilities in NY State just buy power in the market and pass it along with minimal markup, but adjust it 2-4 times a year.
I don't know if the efforts has resulted in lower rates. I do know that when the Utilities were force to sell their power plants, they took the windfall, formed subsidiaries, and just bought power stations outside their service territory. So it turned into a giant churn of power plant ownership. The company you posted "PSEG POWER" is such a subsidiary. They bought power plants in Conn, and a bunch of other locations. They do not sell power to customers in PSEG-NJ or to PSEG-LI service territory.
Unfortunately for the folks in Texas (home of Enron), they were all in and drank the cool-aid of deregulation. When the Market got tight for available power the market price went thru the roof. The ones who's power was rationed (turned off) may be the lucky ones, if they had a whole house generator and could keep the heat on.
And just for example, Texas had a price cap of $9000 per Megawatthour (Mwh). Most states which deregulated have price caps in place also. I think NY ISO market price cap is $1000 per Mwh. But NYISO has market circuit breakers which allow them to "freeze market prices" during a crisis, like a Blackout. It's a dangerous financial place to play for saving 10-20 bucks a month on your electric bill.
PS: Long Island NY is not a deregulated market because LIPA is a quasi govt agency who owns the service territory. And everyone knows the Govt does not like to compete in a market. ;-)