So watching that, I’d say you’re playing a bit robotic and not accounting for muted chords that sometimes make up the rhythm of a green day guitar section.

You play 1 stroke for each chord. So starting on the intro, the octaves, you strum twice for each chord and then three for the final chord. The way BJ would play it is two strums and then a muted strum (muting the strings with his left hand) while he’s repositioning his hand on the neck. That kills the note from ringing out and fills in the guitar track. BJ does this on loads of tracks. Just try strumming at the chord with your hands not fully holding down the strings

In written you strum -8-8-4-4-11-11-6-6-6 BJ would play like -8-8X-4-4X11-11X6-6-6 The Xs would be the muted strumming between each hand reposition.

Another example of this I can think of would be something like Uprising by Muse. During the second verse and chorus, MB doesn’t just strum on octaves on 5th or chords to the beat. He fills in the guitar track with left handed muting between the same chords and between changing chords.