Hmm, that was 100% the cyclist's fault. Not sure why the driver is apologizing, nor why the cyclist is lecturing the motorist. Yes, the motorist is supposed to signal, but the overtaking vehicle is responsible for passing safely, and passing on off-side (on the left in the video; right in U.S.) is technically illegal around here, and much more dangerous than not signalling.
Any experienced cyclist knows how dangerous it is to pass traffic like that, and should prepared to take evasive action in an instant, or pay the consequences.
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