I love this. Alas, I don't have a 3d printer, but this has me wanting one. Being able to organize cables under my desk has been a challenge since my 1st computer. This modular solution seems to fix all my needs.
If you don't have or want to have a printer, try looking for hobbyists with a printer, somewhat in your area. If you contact them personally they might print for cheap and mail it to you.
My wife found someone on the local facebook "Gifting Community" who wanted a "circular sock knitting machine" 3D printed. She paid for the filament, and a couple weeks later (nearly 100 3d printed parts, ~3KG of filament), I finished the prints for her.
Also look for makerspaces or your library. Our library has a 3D printer and you can send designs via e-mail and they will print them and you can pick them up, you pay by weight for filament used.
I have a 3d printer, and I thought the gridfinity system would be awesome, but the biggest problem is that they need to be printed. Printing the plates takes a couple hours per plate. And I don't typically want to be in the same room as the printer when it's running.
This is slightly better because the design seems to be simpler and easier to print.
But I would rather have something that I can buy and also extend.