My question is if SBL is worth that value (and the amount of promo emails).
I haven't done Scott's bass lessons, I do however have a Bachelor of Music degree.
So judging on what I've seen on YouTube, my answer is No.
A lot of his content is generic info that is simply reiterated in a video format.
Try this. Self directed learning.
List the aspects of bass playing that are important to you.
Rate your ability on those particular aspects 1-10 (best to worst)
Flip the list 10-1 (worst to best)
Work on the top three aspects of the flipped list.
Reassess periodically.
That way you work on what you need work on, rather than working on what you are good at.
Just my own history. I started playing when I was 17, never did music at high school, never had private lessons, got myself to a high enough standard to successfully audition to get into university, and obtain the degree using this method.
As for particular exercises the internet has a vast wealth of content available (wasn't like that when I was young) once you figure what needs work, then searching is not difficult from there.
A little tip for nailing the lines of those bands you mentioned.
Set a metronome up to click only on beat 2 and 4 and play with that. It's up to you to state with your playing where 1 is.