That situation is not likely to be encountered by someone who is focusing on writing original music for performing rock shows. It is also not a situation that will be encountered by a bass player who is starting a working cover band.
Theory is VERY important if you are trying to jam with people or you are doing improvisational music but not everybody wants to do that.
BTW, I could have figured out the song you mentioned in one turn around before I knew any theory at all.
I don't know what you call "original rock music" but not all of it is as dumb as people think. Never have I been disappointed with my theory knowledge when trying to play these. I know Avenged Sevenfold likes to use keys of D minor and A minor, typically focusing on the D, A, Bb, Eb, and F chord progressions. They also like harmonic minor, diminished, and chromatic runs. The duel guitar leads tend to be harmonies of a 3rd (or a 6th depending on how you look at it). Save Me has a very complicated rhythm to follow until you figure out the 6/8 timing with the pickup notes. Some of the faster rolls are straight triplets and easier to keep track of that way.
I think music theory has helped me greatly with a number of things and allowed me to pick up music very quickly. I joined a new band recently and was able to pick up 6 of their original songs in one practice. Now when the writer shows us a song I'm able to pick it up by watching his fingers because I can see the chords and progressions and it all just makes sense and it's easier to memorize. It also helps me follow more melodic lines and right my own fills more easily.
An easy trap to fall into though is being theoretically "perfect". At first I wouldn't play any accidentals or anything that I thought was "wrong". That was my biggest obstacle to let go.
https://www.youtube.com/watch?v=dqLPb0_ygKk
https://www.youtube.com/watch?v=0ipv_l7KoSI
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https://www.youtube.com/watch?v=xuT2mQaTno0
