Yeah that's the core idea with all code notebooks like Observable or Jupyter, etc. You get instant feedback and results right in the notebook. So you type some code, usually press a button to run, and instantly see the results right next to the code. It would be kind of like if your traditional IDE had a run button that compiled, ran, and dumped the output of your in development program as comments right below the lines you're editing.

It's kind of like that, but LaTeX compiles to an image you can print out on a sheet of paper. By contrast, in ObservableHQ, or in Gnumeric, you can make a reactive document that responds in real time to something like dragging a slider.

https://observablehq.com/@kragen/plotting-with-a-slider is a really simple example, slightly tweaked from one of Mike Bostock's; you can drag the slider to change the parameters of the WebGL plot displayed below it. This gives you a much faster feedback loop than editing and recompiling in Overleaf. It's way more live than Overleaf.

Also, the document lives at an URL and you can link to it with different parameters. So instead of just being a static document, it's a program that takes its input from the URL, interacts with the user, and lets the user save their work as a URL and send it to somebody else, like https://observablehq.com/@kragen/plotting-with-a-slider?f=si... for example.

And then, as I said, if you want to do a linear regression in LaTeX, you are going to be a very sad panda very soon, because it's possible.