-Quite different scenario. One was shot down by a Russian-made surface-to-air missile (And one can hardly fault Boeing for not providing ECM equipment as standard!), the other was (probably) wilfully flown into the great void.

Here, on the other hand, there are two eerily similar cases where the likely -mind, likely- common denominator is a new 'feature' which has been undercommunicated to the pilots flying the things.