They are different symbols, but messing up each one is an act of speech.

But the message is different! That's the point. People react differently to the message. If AOC and Trump both give a speech, they're both acts of speech - but you would expect a conservative crowd to react favorably to one and negatively to the other.

No one would expect a conservative crowd to react the same way to someone burning a photo of AOC as they would to someone burning a photo of Trump - even though they're both the same medium of communicating an idea, the idea is different.

It's not hypocritical to respond differently to different messages, even if the messages are communicated via the same medium. No one has to like every movie exactly the same just because they're all movies. No one has to approve of every political speech the same way just because they're all political speeches. And the same is true of burning flags.