It's not really meant/supposed to help with general social anxiety. It's really only meant to be used occasionally like before performance situations to help tamper the physical sensations of performance anxiety.
I don't think beta blockers can help with low self esteem or racing anxious thoughts that often accompany/perpetuate social anxiety. For these I believe you need ad's, benzos, cbt, etc.
Nobody, I'm nobody.
I'm a tramp, a bum, a hobo, I'm a boxcar and a jug of wine, and a straight razor if you get too close to me.
Give me liberty, or give me memes!