And I think it comes back to the principles of Slack. By shooting more than you need, you have room to cut. Hopefully, you'll have to wind up cutting good stuff because you have too much good stuff.
I've gone down this road and I don't think that it's good advice any more. The secret to good photography is having a good editor, someone who can tell you which photos you have are good and bad, and why. Someone you can have a discussion with over a dozen 11x14" prints. Continuous improvement. Develop your eye and shoot neither too many nor too few photos. Every time you go through the review process you get a better sense of what you should be looking for in your photos.
It's so easy to fill up an SD card with nothing but garbage. I've done that. I've gone through bulk rolls (100' of 35mm film) and filled them with garbage I just don't want to see any more. By shooting more than you need, you can easily fall into the trap that because the photo will probably get cut during editing, there's no point to putting any special amount of effort into it. So there's no point in shooting more pictures if you're not putting enough effort into each one that it could be good. When I was at college I remember having discussions where we thought that there was not really any point to going through more than a single bulk roll per academic quarter (18 rolls in 10 weeks, or ~65 exposures per week). People who shot less than that much weren't showing as much improvement, and people who shot more than that were just ending up going through the process a bit too mechanically. That was just a rule of thumb for the classes at that particular place and time.
There are good, great, and amazing photographers who shoot such a small number of photos it would probably shock you, and others who shoot so much it makes you wonder how quickly they must go through equipment.
The downside is that I'm usually lazy/reluctant to delete the extras, especially when there's a tossup as to which is the "best", so I end up with tons of photos I don't want in my library.
As a side gig, I take photos of domestic animals (primarily dogs). Some of the animals can be posed like little dolls. Others can't sit still to save their lives. I also take action photos of them. I have to spend time manufacturing perfect, because I often can't make very many on-the-fly changes. But to capture that perfect, I have to take a lot of photos.
As a hobby, I practice general photography, and my usual method is to lock some variables, and take several photographs while floating other variables.
Also as a hobby I practice astrophotography, and here you absolutely have to manufacture perfect, because you only take a lot of pictures in order to stack them. A single photo can take hours to produce, so you do what you can to get it right in the first place.
This method of practicing and improving used to be expensive with film, but with digital the process is now free.
The other thing you learn is your camera shortcuts so that when you do run into a photographic moment you can quickly take a bunch of shots with different settings.