Two things, no such thing as "right of way" and it was a restricted passage.
It's 'stand on' or 'give way' but it's not 'right of way'.

I'd have just ignored him or tigthened up the distances such that the
boarder would have had to chose to manuever elsewhere. Being careful not to
put other vessels at risk, of course. Much like kayaks the operating of
those things comes with the expectation of getting dunked or having to deal
with wave conditions.

In the no excuse category: the guy on a sailboard who came shooting out
out from behind the breakwater yesterday burning hell for leather
through a group of boats, (both powerboats and sailboats running
underpower), proceeding slowly and queing up orderly to pass through
the narrow opening into the marina. The sailboarder headed straight for
my stem, and while I gave him as much space as I could I had no time or
space to change course sufficiently to allow him a wide berth. After he
flipped me off, I watched him "slalom" through a half dozen boats
behind me- passing some to port and others to starboard . Sure, he had
the "right of way"- but he had no cause to behave belligerantly when it
was his *own* choice that eliminated most of the options anybody would
have had to accomodate him. I wonder if he's telling tales about the
arsehole boaters who nearly ran him down when he shot out from behind
the breakwater?