My BS350 (slightly larger but essentially the same) has the same sort of clearance for the blade, also from new. There is a small gap, but as you say it is tiny. But having the wider gap to the right of the blade gives the required clearance when the table is tilted to 45 degrees.
As I understand it, a small gap is ok - as long as there is a gap and the blade isn't fouling the insert. Some people make their own inserts one for each blade they use, and cut a slot with the blade in the machine at the time. That gives a zero clearance insert (but the table can't be tilted away from horizontal of course.
The insert/table can't be adjusted to give more clearance, you need to take the insert out and just file the mouth a little wider, but only if you feel it needs to be a bit larger.
Cheers
Steve