I guess lane splitting/filtering in the UK is so common and generally expected, we'd not bat an eyelid at that. A lot of vehicles including police cars often move out of the way of a filtering bike over here, although we do get the odd car that intentionally blocks us, they are often quickly dispatched with a friendly wave of a middle finger!
looks like it had hazards on, not emergency lights? Although as we only see the car for a short bit of the clip hard to see (and no audio either)