I've not tried Cities: Skylines, so I can't really speak to whether the games are similar or how a re-branding would work.
The EA cryptic response seems to add more questions than it answers. Very interesting... I can see a lot of problems on the horizon if they actually tried to revamp either code. Maybe they're looking to acquire Paradox or Colossal Order in order to get a developer team to finally create another SimCity.
I would love to see a new SimCity; I personally don't care for the whole online thing, but now that they have a few years of what doesn't work under their belt, a city building development team might be able to do a better job than the Glassbox model allowed back in 2013.
*raises hand to be beta tester for any new SimCity games*