I can empathize with your perspective. For everything genuinely useful thing like the Gridfinity storage ecosystem, there's a mountain of future landfill. There's only so many wifi router wall-mount brackets you need.

However, I am going to gently push back by pointing out that you're not connecting the dots between knowing how to use CAD to create solutions to problems, and having cheap 3D printers available that can make those solutions real.

In other words, your mistake might be looking externally for what you should be making. It's not so much a failure of imagination but not training your brain to make the possibility of creating objects one of the first steps on the path to problem solving. Perhaps a good analogy is how people go from asking GPT-4 things they've heard other people try to making asking GPT-4 about everything as normal as brushing your teeth.

So like, as much as it's awesome that I could realize I can print my own reels (for pick and place) from an STL off Thingiverse, my main use of my 3D printer at this point is to print off plastic prototypes of circuit boards and custom enclosures that I'm working on. Not only does this allow me to verify clearance (I actually saved myself five digits and months of pain recently by realizing that the 1/4" audio jacks would not allow my board to be inserted as designed) but it gives me something I can put in people's hands. I've found that, over many years, you can describe things to people and they will nod like they get it, and then when I put the real thing in their hands, they say something roughly like, "oh, this is what you meant". Which I used to find frustrating, and now I just accept it.

Right now, I'm working with the company in China that makes hard shell cases for basically every consumer product. They are sending me revisions of the insert that will hold everything safely. I print them off and then send photos and measurements back of how everything fits (or doesn't) which completely avoids the expensive and slow process of them making a mold, sending me a sample and me testing it. I've literally saved months and thousands doing this. It's awesome.

Similarly, you might have heard that injection molding is incredibly expensive to get started with and that there are fussy design rules you must follow. Well, engineers have recently clued in to the realization that we can essentially 3D print the molds, saving thousands and many lost weeks. Right now there's this crazy arbitrage where about 90% of product designers don't appear to realize that this is a thing, yet.

I could go on and on. The only takeaway is that as you normalize CAD and 3D printing as a go to tool the same way you probably think screwdrivers are pretty normal, you realize that you have more things you need a 3D printer for than things you need a screwdriver for. And that escalation can be really fast.

Addendum 1: Also, remember that it's not just 3D printing. Creating photo-realistic renders of something that doesn't exist yet can save the day. But there's also subtractive processes like CNC which is in some ways even more useful than additive processes like 3D printing. There's a Kickstarter right now for Carvera Air that a lot of folks should get in on.

Addendum 2: One of my very favourite theoretical use-cases for 3D printing is printing prosthetic limbs for animals. I say theoretical because I've never done it personally... but I intend to. I'm a total sucker for this concept and I want to have time to get involved someday. Lots of videos on YouTube, like https://www.youtube.com/watch?v=dP3Kizf-Zqg and https://www.youtube.com/watch?v=EynjYK45dyg and https://www.youtube.com/watch?v=sdFtMRko2GU