Exposure is not how dark or how light an image looks!

Again,

"For every complex problem there is an answer that is clear, simple, and wrong."-- H. L. Mencken

You're entitled to call them as you see them. I've watched scientific and technical experts argue over a great many things — but that's not really helpful to a beginner.

What is helpful are experts able to write and present concepts in a manner which is easily understandable to non-experts.

“It can scarcely be denied that the supreme goal of all theory is to make the irreducible basic elements as simple and as few as possible without having to surrender the adequate representation of a single datum of experience.” Einstein.

That one has a very bad reputation because of many mistakes.

I work with the raw file in Lightroom Classic. That experience, over time with thousands of repetitions, has informed how I interpret and use the JPEG preview image and histogram as references in the field.

How would RawDigger contribute to that goal in a way that my current workflow does not?

I'm intentionally framing this within the context of the photography I do. If you or others find that app a useful tool in your respective workflows, I've no desire to challenge that. My sole objective, here, is to better understand whether or not RawDigger has any potential benefit to me.

I'm confident the workflow I've developed does well at supporting my overarching goal of making a pleasing, high-quality image. While I'm skeptical RawDigger would make a significant contribution to that effort, I'm open to being persuaded otherwise.

If you've never looked at the raw data, how do you know how much headroom you've got in the raw file? You can't tell by the Lr histogram.

Facts matter, not "as I see them".

The only way to tell if it's going to help you is to try it. take a file that you think is perfectly ETTR. Look at it in RawDigger. Is there extra headroom? How much? Is there clipping?

Could be, but since this is a beginners area, they can find some basic concepts which are written and illustrated in a manner they can understand pretty easily. Errors are not all of the same degree of importance and range from minor to major. Some will attempt to make mountains from molehills in that regard, but that's life.

If you're aware of something which needs to be corrected, you can always let the author know.

I do not find LrC's histogram very useful. It does not tell me much about raw data but about the modified image, image modified by selected profile, WB, etc.
Rawdigger's histogram tells me about the raw data. I need the information about the raw data to find the optimal exposure in a sequence of images and to locate if and where the highlights are blown and where LrC will attempt to reconstruct the data using unclipped channels.

The problem is that it contains wrong information that will misinform beginners (e.g., the chapter about diffraction). According to the discussion on DPR, the author has been repeatedly informed about the errors without taking action.

There were repeated attempts to inform the author of his grave mistakes.

How you interpret and describe any given set of facts likely matters more to you than to others. Others will naturally favor their own point of view on any given matter. The art is in persuading others to your viewpoint, because demanding it usually doesn't work well.

In the case of Bruce, that's not possible any more.

Given you are persuaded that exposure triangles are dangerous misinformation, will you edit the link off?

The purpose of a histogram in a raw processing application is to provide data which represents the processed image state. It's very useful in the role it's designed to play in the process of creating images.

RawDigger is informative in evaluating the unprocessed raw data from a captured scene which is used by your processing application to construct the image you will eventually see — after it's been processed. The latent image data in your raw file is not an image until it's been processed into a viewable form, it's raw scene information waiting to become an image.

Alternatively, you could run a series of bracketed exposures to determine how the captured scene is represented in the processed image. A series of bracketed and processed test images can be quite useful in evaluating the end results obtained and obtainable from your imaging chain.

Maybe, I'm not in any rush. I'm only generally aware of the site and I'd want to take a closer look at any concerns to see how serious any errors or omissions might be. For now, from what I've seen of the site and other sources of online resources for beginners, I think a beginner could do a lot worse in getting started with basic information online.

Suggest a better alternative and I'll make an edit to substitute or add the better resource.

And yet, you are the one who recommended it.

This, in particular, is toxic:

"Aperture: controls the area over which light can enter your camera
Shutter speed: controls the duration of the exposure
ISO speed: controls the sensitivity of your camera's sensor to a given amount of light

One can therefore use many combinations of the above three settings to achieve the same exposure."