I assume Yale isn’t broke but idk. Universities are just like any other business where they will cut products that aren’t making money or performing as well as others. The article talks about the course needing many teacher assistants to field student questions and hold labs, and that originally these costs were covered by a donation which has now run out.

It also could just be some internal politics and blaming it on financials is the public reason.

But you’re not wrong that student tuition costs should theoretically go to the courses they sign up for

Yes it is all online for free

CS50 is produced by Harvard and is opencourseware (free) that isn’t going away.

What is changing is that Yale won’t be offering CS50 courses going forward, seemingly due to funding issues.