He seemed to also wait until he thought the television cameras would be off him before hitting his horses.
I really don't think he was taking time out, in the middle of a 4* cross country course, trying to shave every possible second off his time, to consider where the cameras are, and whether he'd be in front of them at that moment 
More likely, he was trying to sharpen his horses up (and make time) between fences, rather than taking their mind off their job during a complex combination of jumping efforts. Most of the cameras point at fences, because they're the interesting bits to show. Natural consequence...
Would you be happy to read in the papers tomorrow that OT had done something awful to himself, @cobrider? Would you feel that was appropriate justice, or retribution? I don't think that will happen, because I don't think he's likely to react in that manner, but with the sort of response on social media, and another rider, I think it would be a real possibility, and I would be horrified to see it (regardless of which rider they were, or my feelings on their conduct).
At the end of the day, the horses have, as far as any animal can, a voice - that's the FEI's warning, their inspection of them the next day (and any possible escalation had the horses actually suffered in any tangible manner), the response of the BHS, and every single armchair eventer person spouting their opinion on social media. Each one of those voices is - or claims to be - speaking on behalf of those horses - and that's good, within reason.
We should be compassionate towards our horses - within the boundaries of what is good for them. We should also be compassionate towards our fellow humans - not accepting their every action, but just remembering that they might be suffering now too.