For me at least it’s mainly because he’s undeserving. Quite clearly not the best driver over the course of the season – he’s simply been in the best car. I note that LH hasn’t been in the best car this year, because unlike NR’s car his hasn’t been reliable – that is the only reason NR will win the championship. I suspect a lot of people feel the same.
Button would drive rings around NR – he has talents Rosberg simply couldn’t dream of. Strangely enough he’s also far from being mr consistent – on his day he is simply unbeatable by anybody else even if they’re also on top form, but those days don’t happen all that often (apart from when he was in a standout car).
This is the thing – I’m a Button fan, but happy to acknowledge that of those WCs currently still driving Alonso and LH are definitely better and Vettel might be, but NR isn’t in the same league as any of those.