Can we use online video lectures to free university professors from lecturing for lower-division courses in mathematics?
Yes, you absolutely can!
The win-win is very unlikely though. Students won't see lower tuition or anything, and will have no opportunity to interact with anyone at the faculty level (so no letters of recommendation, no research jobs, etc). Professor lines will be closed on retirement (or through layoffs) because who needs them, we've got McGraw-Hill eLectures.