i am sure others will say this better/more cohesively but this was the general narrative i got from All That:
The black parade gets pulled back to perform + also be the ones narrating/directing executions. they are also the ones providing a soundtrack to the nuclear war that is going on around them.
Gerard is resisting this, as seen by how he mocks the guy with the rose and gets slapped for it, then takes off his jacket and reads a book and then gets literally manhandled back into his jacket for teenagers.
teenagers is very specifically the soundtrack to propaganda the band is being forced to perform, with commercials/reality tv/talk show clips going on behind them.
this is followed up by a an angry rendition of disenchanted, where the very prominent dictator and flag imagery serve as an example of exactly what the band is disenchanted about/what they oppose but are being forced to promote.
In famous last words the band, lead by gerard, make a stand against the dictator and refuse to participate. as a result gerard is executed onstage and the rest of the band dragged away to meet a similar fate.
EDITED TO ADD:
prev yes this is an important addition!! especially bc the deer was sort of the symbol of draag but!!! it decayed!!! it rotted away to nothing!!! there’s definitely meaning there as well! like. rogue 1 kinda vibes. they all died but their resistance was instrumental in bringing it down.
