Why is it SRU?

[Preditor]

Perhaps the reason for calling it such a generic name is to allow for your own expansion on it?
EG: I've never heard of the 'Corleones' per se, but their appearance is quite obviously 'Organised Crime Family/Mafia'.

Following this, it reduces pressure on modellers/devs. Yes; you can ask for improvements you've thought of, but because the SRU are fictional, you can't base suggestions off of the real thing: 'irl the SWAT have rocket launchers lol XD'

TL : DR SRU name is generic - allows for your own expansion. Lowers expectations on what they actually are.

The Corleones are from the Godfather or something like that I think.