Why is the Origin in Body and Part mandatory?

[Jolbas]

So let's see if anybody else is here around feeling the same as you

Yes, we'll see. There's no massive cheering so far

I'm also hoping for a little more technical answer of why I'm not allowed to delete those Origin elements. Are there essential parts of the program that are fully dependent of them?

[drmacro]

...Are there essential parts of the program that are fully dependent of them?

Yes.

[GeneFC]

I'm also hoping for a little more technical answer of why I'm not allowed to delete those Origin elements.

You are allowed to delete the origins.

After you do so be sure to look up the recent forum Help topics where users accidently deleted the origins and found everything broken in their models.

Gene

[chrisb]

I "succeeded" in deleting an origin. Now nothing really goes. I can't even delete the broken Part container.

[adrianinsaval]

Yes, sorry. I forgot to uncheck the "show all". I wasn't going to change them but I thought they could be read only, which would actually protect them.

yes this is kind of a bug IMO, they should be read only.

[Jolbas]

I "succeeded" in deleting an origin. Now nothing really goes. I can't even delete the broken Part container.

Yes, thats a broken document. I don't know how you removed the Origin from the Part.
Here's my take using the Project Utility. Removed Origins from Part and Body. Everything works well as far as I can see. You can of cause not attach new objects no the non existing Origins but if you attach to other objects it works.

There are warnings but I don't see any failures.