The second part is indeed wrong: most consumer energy markets have a wholesale market and grid operator, and the grid operator is ultimately responsible for the call on brown-outs. The companies that sell electricity retail to invididual homes are generally buying on that wholesale market, but they're not in a position to cut off their customers: there's straight-up no mechanism to do that on a moment's notice, because the grid-level control doesn't overlap with the retail seller's customers (these retail companies are often basically just a financial instrument that turns the combination of variable wholesale and grid operator fees into a fixed price bill and some customer support: your neighbour can buy from a completely different company and if anyone wants to shut off you but not them they need to come to your house and physically disconnect the lines). What happens in a situation like texas is that the retail companies who are selling at a fixed price start losing money fast, and can't really do anything about it in the short term. If they've built up enough of a buffer from their margins, they may survive, or they may go bankrupt and their customers will need to move to a different provider, but that's a process that takes weeks to months, not minutes in a price spike.

(A similar thing happened in the UK: there weren't any brown-outs, but the spike in wholesale energy prices sent a lot of smaller retail energy companies under. If you were with one of them, like I was, you had no interruption to your supply and in fact won out compared to those on variable tarrifs: the losers were the investors in the retail companies and those who they were unable to pay).

I will agree in general though: unless you have particularly unusual energy consumption habits, or think that the energy market will go up more than the retail companies thing they will, you'll probably win out on a variable rate contract over time, especially if you have a battery to time-shift your consumption (And with the most common UK provider for this, there is still a cap on how much you'll pay, even if wholesale prices skyrocket like they did in Texas).

> if anyone wants to shut off you but not them they need to come to your house and physically disconnect the line

I'm not in the UK, but I gather my utility can do a radio controlled disconnect (they may need to come onsite to reconnect). I would hope that wouldn't be used to enable a virtual brown out for customers of a particular energy marketplace, but I think it's a capability of many communicating meters.

> they did this in Texas

That is not what happened in Texas. The REPs had zero say to do a rolling brownout. "Rolling" outages which became semi-permanent outages were done by the delivery companies, not the retail providers. Retail providers can't just choose to stop selling me electricity for a few hours because they think it's too unprofitable for them, that's not allowed in the contract. My REP at the time probably had some massive costs due to customers like me which didn't lose power; they folded and sold the contract to another company.

> On a variable rate you can choose to cut yourself off or not.

Once again, you clearly don't know what actually happened in Texas. Several people I know on variable rate plans lost power for days.

But hey keep speaking falsehoods instead of actually learning what happened.