I'm biased, of course, but my view is that the L.A. Lakers have not won 17 titles; they've won 12, and the Minneapolis Lakers won 5.
Splitting hairs? Maybe.
But is "franchise" the same as "team"? Franchise, to me, seems like nothing more than a legal entity, a piece of "officialness" that doesn't really translate to the everyday "real world" in which most people experience life.
Should present-day OKC fans claim that their team has won a title? I don't think so. Yes, the "franchise" has won a title, but why should the history and activity of the Seattle SuperSonics apply to the life of the Oklahoma City Thunder and Thunder fans?
The distinction with the Lakers might be less obvious because they kept the name "Lakers," but should basketball fans in Minnesota feel like they have 17 titles because of the 12 won in L.A.? I'd say no. In which case, it also shouldn't work in the opposite direction, with L.A. fans thinking they've won 17 titles.
Another factor complicating the issue is that the NBA doesn't treat every situation the same. For example, they give the 5 Minny Lakers titles to the L.A. Lakers, yet the history/records of the original Charlotte Hornets don't belong to the Pelicans, who used to be the Hornets, but instead were given to the newer Bobcats/Hornets franchise. By that logic, if the L.A. Lakers were to change their name, and the Timberwolves then became the Lakers, the 5 Minny titles should/would go to the new Minny Lakers.