Although the massacre of the Romanovs was a moral failing, it does not delegitimize the right for the workers, peasants, and soldiers who suffered under the feudal class dictatorship that saw them as expendable, to rise up for their freedom from such a system and towards their own self-government. Denying this is like condemning the end of slavery in North America because of slave revolts.
I wouldn't call it a moral failing of the revolution but an act of necessity to defend themselves from the wolves that would use any one of these children as a symbol of the Russian Empire to revive it with the support of every monarchy in the region. I mean just look at Miami and how bloodthirsty the children of gusanos are for losing their plantations, I can only imagine how bloodthirsty a child denied their right to an empire would be.
I don't know what kind of calculus exists to actually prove this or that. I'm skeptical since the reactionaries will invent their own justification absent an actual living Romanov anyway. But all I wanted to state is that this act, unsanctioned by the Bolsheviks themselves, doesn't delegitimize the revolution
Yup moral failing of their parents to say God says this kid gets to rule you.
Morals didn't come into it. They had already abdicated the throne and were in custody of Kerensky's provisional government before the bolsheviks took power. And the bolsheviks didn't kill them because of the moral failing of monarchism, but because they were worried about losing that custody to the white army. The decision was entirely strategic, rather than being intended as an ideological blow to some perceived moral failing.
I don't mean this as an "own" but as an accurate recounting of the reasoning that went into the decision.