I haven't seen any of the meeting, just reading comments on here but I'm not particularly a fan of video replays. Plenty of contact is made in the sport but much of this is not enough to create a fall but unfortunately I think replays encourage riders to do exactly that as they know they'll get back in the re-run. I've seen it so many times, from Harris in a British Final to Nicki P & Hans A in GPs. Those who choose to stay on, as they should, can feel aggrieved but to fall on purpose risks injury to self and others. There shouldn't need to be a fall for exclusions to occur.
As I said, this is not about this particular incident as I haven't seen it.