Apologies if this is a repost, didn't see one after search

Edit: I haven't read much into the btc white paper or code but, as a layman I believe Dimon's comments may be a fundamental misunderstanding of how btc's blockchain and "decentralized" nature works

He understands very well what it is and how it works. He realises it's an enormous threat to his beloved money printer, and so he's using his high profile to play up to people's fears and sow seeds of doubt.