That would not be the best explanation at all.. To say 'there is something faulty to the tank' or 'Russian tank crew training program' isn't on par with other countries isn't very logical step finding out why the tank stalled regarding this particular incident. .
This 'break down' incident only happened to one Armata and not to multiple Armatas. Therefore can't necessarily be reflected upon the whole fleet to say 'there is something faulty to the tank' or that particular tank. Especially when it did not break down at all.
As of the weak tank crew training as a best explanation on why the tank stalled, I would not think that since there is no evidence or statistics of where multiple tank crews of the Russian armored division fails to perform duty..
Instead of jumping to the bigger picture straight away, It is better to start at the smaller picture. Take a look at the particular driver himself first on why he doesn't know about the brakes, and also the whole tank crew themselves.
So far in my view this incident appears to be an isolated case of a driver failing to know his vehicle's function.