$72 for the 12 episodes that will be exclusive to CBS-AA, playing out over only 12 weeks (11 for 2 part finale at once) leaving you with months of stuff you don't want, that you'll loose all access to including Discovery, is a little much if it is one fixed year.
Because people don't want to pay another $9.99 a month just to watch a Star Trek show or spending $9.99 a month to watch programs they'll never ever watch on top of their already too high budget of paying monthly subscriptions.
Wait until all 15 episodes have been released, and then subscribe. If you're ambitious, you might have all 15 episodes watched before the free trial ends. Just a suggestion.
You know it ain't gonna be easy to cancel CBS
Actually, it's pretty easy. I've subscribed on-and-off for awhile now, and it's literally just a matter of going to your account and unsubscribing (a click of a button). You get access for the rest of the period you've paid for, and after that they stop charging you. Seriously.