I don't think Russian state media should be editing Wikipedia entries especially not on matters of current affairs.
But still, interpreted literally the new statement is far more factually correct and unbiased than what it replaced. Whoever shot down the plane, they were "soldiers" or fighters of some variety and almost certainly can be described as Ukrainian, given that everyone seems to agree that the fighters are actually eastern Ukrainians and at most Russia is supplying weapons to them.
The original text, on the other hand, more or less exactly sums up western/west Ukrainian line despite the obvious abuse of the word terrorist to mean "rebel fighter" and the [citation needed] assertion about who did it and the source of the weapons.
I don't think Wikipedia should be used as a political tool fullstop. posting accusations that Russia was involved is for news sites not for supposedly unbiased material. If it proves to be a fact then it can be put there. The original text is more like a fox news story than an encyclopaedia reference.