For the courses that are going to be discontinued, will the respective videos still be available on YouTube?

I can't speak specifically to those topics.  I can tell you that, in the past, it has depended on who owns the rights to the content and what the owner decides..  Some topics, like Python Programming, remain on KA's YouTube channel.  Others, like one of the music courses (I don't remember the name of the course), were posted to the creator's YouTube channel.  Other courses were not posted.

Typically, when courses are discontinued, announcements are posted that let you know whether the content is available and, if so, links are posted as well.

Hi Eddie,

There's not an explicit plan to remove the MCAT videos from Khan Academy's YouTube channel, but we can't guarantee that they will still be available after September 2021.

We understand that these videos are important resources for some students and removing the MCAT course was definitely a difficult decision for us. However, doing so will allow our content team to continue prioritizing additions and improvements to core K-12 courses so we can continue to provide a free, world-class education.

Thanks for being a part of our community! Please let me know if you have any additional questions!