It is not a bad idea footprint wise for coffins to be standing up. At first glance the screw-in capsule sounds like a revolutionary idea too, it could save some time and effort with digging as well as burial space. In practice it wouldn't work so well and a pre-hole would need to be done with some machinery. Second, the cost of the capsule, considering it would be made out steel would add up quickly too. Still, coffins standing up to save space would not be a bad idea though I would rather be cremated so as not to contribute to funerary industry.
I'm trying to picture the whole burial process with the capsule and find it somewhat comical. Would the family of the deceased have a ceremony before the capsule is screwed in, after, when it's half way in?
Steel costs 50 cents a kg. You could probably make do with a rough casting of cast iron. It might cost US$100. By contrast current coffins commonly exceed US$5000 in rich countries.
I think the ritual and symbolic concerns you point out are a much more serious issue.
How are you going to get your corpse cremated without involving the funerary industry?
