I don't see why that's even remotely a bad thing or whose intelligence is being insulted. Alternate timelines and universes are nothing new in Trek.
Yes, but the logic of the universe is so fundamentally different it makes it a little irksome, to me, to have that physical link of Spock. If it's a clean reboot, they shouldn't be able to ask original-Spock if he's ever met a guy by the same name as the guy they met. They should have to figure it out on their own. (And BTW, that was a HUGE story copout. "Hey future me, this guy we just met, is he evil?" Lame.)
And I do think the recency and size of Star Trek fandom did make it a production necessity to link to the prime universe. It gave just enough of a hook to make it more palletable for fans that the movie is doing its own thing. Whereas if, say, TNG/DS9/Voy/Ent had never happened, they could have just rebooted nobody would have cared.