Huh?
Apart from several discrete neighborhoods like every metropolitan area in the US, San Diego has a ridiculously low crime rate compared to national averages. The Bayfront area from Harborview all the way down to Seaport Village and the Convention Center is undergoing another building renaissance with new hotels and restaurants under construction everywhere. It's an area already home to half a dozen 5-star hotels and numerous Michelin Star and James Beard award-winning restaurants. Can the Gaslamp look like Bourbon Street during Mardi-Gras? Yes, occasionally (and usually during ComicCon surprisingly), but it's still a very safe, if crowded, and vibrant area to explore. Plus, you have Coronado Island just across the bridge with the Hotel Del and all of the amazing shops and restaurants around it. It's not like they would be building it in Barrio Logan or San Ysidro or Kearny Mesa.
Compare that with Port Canaveral, which, aside from the awesomeness of the Cape and Kennedy Space Center, hasn't seen much change since people were parking on the beach to watch Apollo launches and maybe see an astronaut driving his Vette. It's not a "bad" place, there's just not a lot else there beside the space complex. Plus, it's only a 45 minute drive from Orlando so I don't see why they'd bother building so close when they can keep people in the WDW bubble and get more money spent in Disney-owned shops and restaurants.
I could see them maybe building something in Miami and originating more cruises there. Miami's cruise terminals are the most state of the art in the country and cruises out of Miami give you greater access to the Western Caribbean too. Or, on one of the private
DCL islands, but Port Canaveral doesn't make much sense as a destination based on the surrounding area and proximity to WDW.