No, it is not legal to do so.
Attending or graduating from an interior design program calling itself “Interior Architecture” does not give one the right to use the title “Architect” or “Architecture” in their descriptions or activities.
The term “Interior Architect” is not a real profession or title.  This language is used as a marketing tool by some universities, national interior design organizations, examining bodies and accrediting bodies, likely thinking these titles somehow elevate the profession.  Using an illegal title  does nothing to elevate the profession.
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