The purpose for internship programs generally are to grow the interns skills and establish a talent pipeline, _not_ for their immediate "code lift".
Unless you think that AI is going to completely replace developers, then there will remain value in having interns.
My former FAANG uses internships at the Ph.D. level for both recruiting and talent acquisition. Hiring committees have a way easier time assessing candidates with feedback like "this intern implemented X, Y, and Z beyond their project spec W during the summer" or "this intern goofed off all summer."