Captions are how students study now
When researchers ask students whether they use captions, the result is consistent: a majority of students with no hearing impairment use captions when available. Reading and listening together encodes better than listening alone. Captions are no longer 'an accessibility tool for some students' — they're how all students study.
When transcripts are searchable and persistent, they become the highest-utility artifact a course produces. A student preparing for an exam can search 'Calvin cycle' across the entire semester and land on the exact two minutes where the instructor explained it. That's a fundamentally different study experience.