I don’t think that’s a fair assessment. The document was meant to be a living adaptable document. In many cases rather than adapting the document directly, laws and interpretations were layered outside the document to keep most the initial structure solid. Amendments came about largely once something was deemed so important it absolutely should be embedded (like the abolishment of slavery) so few mistakes could be made.

The structure should really have a few more obvious significant layers where things could shift around over time.