Guards aren't necessary for soviets to be competitive they're just in three very good commanders and are easy to use with attack move and merge.
The garand or bar rifleman could use a buff but they can still have access to two good commanders that unlock the m1919 which makes them competitive.
Soviets play fine in 1v1, it's larger gamemodes where guards are necessary to make a difference with infantry. Otherwise Soviets have to rely on their tanks or bleed themselves dry with penals for only a mediocre performance against axis elites. Make no mistake, conscripts are very useful in 4v4, but in the late game there are slim few situations where they can attack and be useful. They are mostly only good for snaring, defense, and merge by the end of a match.