Although I bought it with TSW5, the route is missing in TSW6. I am aware that it isn't available in the shop any more, but I PAYED for it !
Within the first month after Train Sim World 6 launches, we’ll release unbranded versions of the following add-ons. If you already own the Caltrain-branded versions, you’ll be able to download the unbranded versions for free on the same platform and account. Peninsular Corridor: San Francisco – San Jose MP36PH-3C Baby Bullet MP15DC Diesel Switcher This is how it was announced
Have a look here: https://forums.dovetailgames.com/threads/peninsula-corridor-content-in-tsw-6.93940/
Thanks, I was aware of that solution. I just wanted to know WHY it didn't show up in TSW6 and martin#2729 explained it.
HOWEVER, you can copy your Caltrain files from TSW 5 and paste them into TSW 6, and they'll work fine (this is a way to keep the branded versions after the new ones release)