The true meaning of the word 'Agnostic' is that the nature of God is unknown and cannot be known, so in that sense an Agnostic is a believer of sorts. That said, an Agnostic is now assumed to be a 'don't know' which still suggest a modicum of 'belief'.
'Why make a strong assertion either way?'
Until such time as tangible evidence is available, why not? I don’t believe in fairies either - but if someone comes up with definitive evidence of their existence I promise will change my mind.
Frankly, the only reason the Abrahamic God is the focus of western attention is because that is what our culture teaches. Had we been born into a different culture we'd likely have considered other Gods miraculous creators and Jehovah/Elohim/Allah/God - whatever you want to call him - to be a non-starter, relegating him to the realms of mythology along with the Greek, Roman , Egyptian and Aztec Gods.