Kurusu,
That is the nearest spot/point for gas to escape, for sure.
A portion of gas can escape around the gap between any style striker and the breech block; but not due to the presence of the fluting cuts - but due to the normal tolerance between the two parts.
As I wrote, some cuts could be long enough/deep enough and could function that way.
Retract the pin all the way and see if you can see the flutes; most of the time one can't, but occasionally a groove does reach that point.
My basic point is that gas relief is not the primary reason or intended purpose for the flutes-which is to provide a place for grease/oil/debris etc- and keep the striker functioning; if they relieve gas it is serendipity at work. JMHO.
