I guess theoretically true, but if they think my images don’t look good so they just move on or aren’t interested, seems that’s a problem for me.
Then don't show your images on a media of which you can't control to people who would move on if their method of viewing images if flawed.
The challenge of trying to get normal end purchasers to understand and do this seems pretty daunting. Bill Atkinson a few years ago I believe tried this, he had a calibration page on his web site with a step wedge with instructions on setting the density. I notice he no longer has this.
There is lots of things Bill doesn't have on his site he had in the past. Also, maybe he's given up attempting to do what you hope to do and has moved on trying to get people viewing his images
incorrectly to fix their end of what is their problem.
There's nothing you can do other than explain to this group how to understand if their display's are incorrect and fix it.
I have a display that is correctly calibrated and profiled specifically to yield an image which matches to my fairly well trained eye what I get on a print.
But prior to soft proofing for output, the images look good. And after soft proofing, the images and the print look good. So your RGB values are good! You're now proposing to make the RGB values wrong so they look good on other's displays that are wrong. Two wrongs don't make a right. And further, the people who's displays are correct will see the images looking wrong. How is that a good fix? It isn't.
My goal for my display isn’t to display my work, it’s to help me predict what my printer is going to produce - and to be honest isn’t ideal for some other things typically done on a computer.
The goal covers both! It's to ensure the RGB values
are correct.
To the 99.999999% of the world out there to whom I hope might stumble across my work (wishful thinking, but we all have to hope), I know that odds are pretty good (95%? 98%? 99.9%?) their display is substantially brighter than mine, and similar probability it is a little bluer than mine, just because I’ve seen many times what the default is for displays and operating systems.
That's simply a huge assumption on your part. Short of going over and viewing you images on 95%? 98%? 99.9%? of potential users displays, there's no way to know what they have their displays set to. Some will be using 12 year old CRT's that can't hit 70cd/m2. Some will be using new LCD's set at whatever came from the factory that might be producing 250cd/m2. Some will be using wide gamut displays outside of an ICC aware web browser. You simply can't predict what all those people see short of looking at your images on their systems. Do you really think this group of users all have the displays close to each other, but somehow, your display is 'wrong' despite a match to the prints which you state look good? This entire venture if fruitless. If you provide them something they can view that isn't ambiguous, like a step wedge, at least you've given them the information they need to see how bad their display is, but probably will not act on to alter the display so it's providing the correct RGB values correctly. And the step wedge isn't going to help with color a lick. So you have one person who's CCT white point is 6500K and another who's viewing the same image at 9300K. There is absolutely nothing you can do about that.
You print the best quality image possible. How does it appear to the observer viewing it under a 6 watt nightlight bulb instead of using proper illumination? Too dark. There's nothing wrong with your print, there's something wrong with an idiot who would view a print that way and further, say it's a poor print because it's too dark! And decide not to buy that print because it's too dark.
So rather than continuing to swim upstream, I began considering if there should be slight tweak for a file that is specifically purposed for display on all of those systems out there that may yield a slightly better result for those viewers, but still would look OK for someone whose display is set a little dimmer or in fact is calibrated and profiled.
Pointless but if it makes you feel better, if you really believe that tweak will apply to more users who might view your images, go for it. It will at least make you feel better.