This is not quite correct. An mRNA vaccine that creates healthy antigens will fail because it won't do anything, not because it will trigger autoimmune issues.

This is not quite correct. An mRNA vaccine that creates healthy antigens will fail because it won't do anything, not because it will trigger autoimmune issues. Your cells are already covered in normal antigens, and your immune system already knows to not attack them. It is true that it is difficult to find the right antigens to target, but the reasons for that are more complicated.