I think it's because his defining trait, in my eyes anyway, is his competence. He's just a good, solid, player who runs a game well. He'd be a pretty marginal selection for best flyhalf in the world, so saying he's the best player is just a bit eh.
I think he's had an excellent season though. Top point scorer and equal top try scorer in the 6 Nations and led Ireland to victory where they probably started the tournament nowhere near favourites.
MOTM performance against South Africa on the weekend in a big upset.
I think there's a big difference between NH and SH fans in terms of how we value players. We seem to give very little credit to kicking games and goalkicking.
If this was an Aussie list we'd probably name two backrowers and three outside backs every year.