No

Something must have been lost in translation because this doesn't make sense

Maybe because the closest substitute costs 900,000 baht upfront.

I just told them I have DTV, which was fine - presumably, it comes up on their system anyway.

It's fair and reasonable, if you're a convicted fraudster with a lifetime ban on opening a bank account.

I'd like to get a Smart Visa next but it's more hassle to apply.

It's inconceivable that the authorities detained you over such a minor matter, which begs the question, who did the dragging? Regardless, the solution is obvious and easy - pay the fine and it's done. It surely wasn't even necessary to come here to figure that out, but now you're here, please explain more about this bizarre story.

I doubt many people move to a developing country, known for regular political upheaval, expecting everything to be the same in 5 years.

You should live in Thailand if you believe you will be happier here than in other countries. Visa conditions shouldn't be a major factor in your decision-making process.

electricity costs vary a lot depending on the aircon unit and how often you use it but even at the top end for a small condo, it should be more than 5k baht/month - water is basically free - but for retirement, always remember that Thailand is still a developing country with costs and prices that should converge towards developed countries over time, so if you plan to be alive for a while, be aware that everything could be much more expensive in 10 or 20 years