Snipers aren't self sufficient in live. They always need support so they don't get rushed by vehicles and killed or rushed by infantry and being pushed off the field after only inflicting 1 kill.
In the patch version they don't just need infantry as back-up, they need the infantry to actually advance into the enemy LoS to do any damage. It makes the Snipers unable to perform one of their primairy functions of clearing HMGs and other infantry from buildings/entrenches positions before assaults.
Except they are. If they have a LOS that is equal to the weapon range, they are self sufficient. Being easily killable does not make them non-self-sufficient. It just makes them vulnerable. Being able to clear HMGs on their own is by their definition, self sufficient. It's not my opinion, it's not semantics, it's just a definition.
Your words: Snipers -> primairy functions of clearing HMGs
Can they do it on their own right now? Yes == self sufficient
Primary function is a singular, it's nonsensical for multiple primary functions to exist but let's assume that one can have leeway and define another role for sniper to bleed enemy units and check if it's self sufficient at that too ATM.
Rifles range on all infantry units: 0-35
Sniper range: 0-50 --> Sniper is still self sufficient.
Don't mix vulnerability with self sufficiency. Regarding OFFENSIVE roles, self sufficiency has nothing to do with needing support.
Sniper is non self sufficient (ergo, needs support) when it comes to it's defensive capabilities.
However, one could argue that no unit is self sufficient in that regard. KT needs support, elefant even more so. Obers, volks, rifles, paks, ZiS guns.... etc. No unit is self sufficient in both offensive and defensive statistics.
If you can think of a counter argument to refute it, I'd be more than willing to hear it.
EDIT: One thing a sniper is not self sufficient in the offensive is: Can it kill tanks? No. Needs support, not self sufficient. Get the jest?