The guy in the bassboat was being an arse. No, he would not have moved in on another bassboat like that, because he knows he'd have soon either had a boarding party or a 3/4 oz RatLTrap headed his way. I guess kayakers aren't as intimidating as a good ole boy in a 21' Ranger?
It's obvious you found a really good spot, because he knew how good it was and decided it was worth showing his arse.
I always give kayakers the right of way when I'm fishing from my bassboat.... it's a much bigger challenge in a kayak to get to a good place to fish, maintain your position, actually fish, etc. In my bassboat I can run and fish literally anywhere in the lake. A guy in a kayak has to break a sweat just to get across the creek. I figure if you expended the effort to get your kayak to that spot, it's yours for as long as you want it.
Those are some dandy smallies... 18" is a fine fish anywhere around here.