I know all places you have mentioned above, quite well. The wait at Sesuit Harbor hasn’t been as bad, but it used to be awful.
The Cape is a culinary wasteland like you mentioned the choices are fried fish, lobster rolls, or mediocre pizza.
Says a chef?
I always thought the Cape/Islands were a bit of a throwback, traditional, and a bit old-fashioned. Relaxing downtime with beautiful, often tidal beaches, water that will numb you, nice golf/tennis/outdoor weather, sailing, paddleboarding, and biking trails galore.
Cutting-edge trends? Oh hell no. The only modern trend is where to park NYC investment banking/PE returns - most often Nantucket, but Martha's Vineyard, parts of Cape Cod, etc.
Food is most often seasonal shore cuisine - yes, most often average to good, where one pays for location, sometimes exorbitantly so ($50,60,70+ per entree).
The Northeast produces too much wealth chasing too few places. I am always impressed by Nantucket. It's beautiful, but maybe it has a 75-day season? May is awful. Most of June is horrible as well. It sticks out into the Atlantic, surrounded by water temperatures of 50 to 60 degrees early on, which creates fog and marine layers until July. Martha's Vineyard, Chatham, and Provincetown can be similar. Me? So many people want to spend $500-1500+/night to sit in a fog bank, interesting. (There are not really beach hotels in San Francisco for this reason).
However, it is beautiful AC during July and August. The hidden season is September and early October, when there is less fog, relatively warm water, and no crowds. And the cranberry bogs are special.
I did the
Figawi boat race from Hyannis to Nantucket over Memorial Day Weekend. Fun, casual, boats of all types, and horrible weather.
If I could volunteer one restaurant that rises above others, it would be Water Street Cafe, Woods Hole, MA.
https://www.waterstreetkitchen.com/ People will line up at 4 pm to try to get a spot at the bar if they do not have one of the few tables reserved.