defstructs and packages

Why CL includes two non-orthogonal concepts for code organization? Why to define an IMAGE package I have to separately declare (defstruct image-state ...)?

Can we replace defstructs with packages in future Lisps?

Also, CL has no privilege management. You can't have sandbox package with restricted rights for unsafe code. Neither you can use packages as EXE files. So you cant use CL as a base for operating system.