What's the packaging look like? How detailed are the digital instructions? What's stopping someone from spending 30 minutes and releasing a free PDF of how to make this?
Heya! I'm not sure the IC stage is the stage where the packaging and instructions have to be showcased already.
The entire LEGO community works with purchasing and downloading PDF's for making MOCs (My Own Creations). And I'm sad to hear that you think this project only takes 30 minutes to make a PDF for. As the base kit is fairly simple, it did take quite some time to get it the way I wanted it to be including the add-ons, while still using bricks that are well accessible on the aftermarket.
$10-$15 for instructions.
Pardon me?
If you really wanted to you could just like make a massive mold of all the pieces and just cast it with resin and it would probably come out cheaper.
That is most definately true. Though for a lot of people the fact that they are LEGO bricks means something.
Bricklink and Toypro literally exist for you to get individual Lego pieces so you don't need to 'scrounge' around for them.
Even Lego themselves allow you to buy pieces: https://www.lego.com/en-us/page/static/pick-a-brick
That is the best source of getting bricks. Although you still need to know exactly which exact pieces, how much and in which color you need them. LEGO does not provide a large variety of bricks in all colors. It's not like you can buy every known brick available from them. Next to that they are more expensive per brick than using the aftermarket like bricklink.
I think people might enjoy the fact that they dont have to look for every individual piece, but just get the case without having to put too much effort into it yourself. If you want to make your own case, have the know how and got the time to spare, I'm not going to stop you! Thats the idea of LEGO, its for everyone!