I don't see a difference between a 'blindspot' and racism but if it is easier for left wingers to accept that he has a 'blindspot' then I suppose we have to take what we can get. I (and alot of Jews) do believe that the guy is an antisemite and I don't see a difference between his racism and that of Nigel Farage's or Boris Johnson's.
Noone has a'blindspot' on their negative/discriminatory attitudes towards People of Colour, they are just racists.
Anyway, I have nothing more to say as @BleakRefs has thankfully summed it up perfectly. Good on Kier Starmer for standing up for Jewish people and listening to us, long may it continue. The Stormzy thing was definitely cringe though