Although I don't own one of the bikes and never rode one either it looks to me as if the chain gauge does not match the sprocket. The sprocket is a lot narrower than the chain.
I noticed that too.
It does not look right at all!

As I said the large amount of side float in combination with a chain rail and / or a chain tensioner which guides the chain sideways prevents the chains side plates from touching the sprockets and thereby reduces mechanical chain noise.
The problem with some of the BMW engine seems to be that the chain guides did not work reliably.
I don't think it's an issue with manufacturing tolerances unless all bikes grind the chain pins and the difference is only if they grind it just enough for the chain to fail if some manufacturing tolerances are on the wrong side.
The more likely scenario is that the guide rail which is supposed to keep the chain channelled where it belongs does not work reliably. This would explain why both right and left timing chains seem to be failure prone.
Does some one know if any components around the timing chains such as tensioners or static chain guides were superseded? It might be a good idea to look into the possibility of a preventive replacement or at least compare the old with the new part to establish the failure mechanism.
And since some of you are probably waiting for a nasty anti - BMW comment let me relieve the tension:
A Japanese engineer would have used a
silent chain.
