Here is an article from yesterday saying that the Philadelphia 76ers want to leave the Wells Fargo Center in South Philly when their lease is up in 2031, and build their own arena at Penns Landing on the Delaware River front.
https://www.inquirer.com/news/philad...-20200826.html
I don't think this is going to happen. Penns Landing is a notoriously difficult place to build. It is where grand urban planning ideas go to die. Traffic and transportation are nightmarish. A basketball arena would only make matters worse. And myriad other issues exist, too many to list here.
If they are going to leave the Wells Fargo and build their own arena, I would bet that they would move to Camden or somewhere near it in South Jersey. The team owners also own the Jersey Devils of the NHL, and seem to have a definite NJ bias. NJ has been without an NBA team since the Nets moved to Brooklyn. And there is a substantial fan base in Jersey for the Sixers. I don't think they would move the team to North Jersey and share the Devils' arena - I doubt even the New York area could support three NBA teams, and it would make no sense to leave the Philly area without a team at all.
But another possibility would be to build an arena in North Philly. The North Broad Street corridor is (or was, pre-Covid) heating up substantially. The renovated Met theater, the Divine Lorraine Hotel, and other developments all point to that section of town as being the next hot spot. Even better, they could build a bball arena on the site of what used to be Baker Bowl, where the Phillies played for 50 years, from 1887 to 1937. There is a subway station there and a regional rail train station (that has two train lines going through it). And they could share the arena with La Salle University, whose current arena is a glorified high school gym*. (Temple University already has a basketball arena, the Liacorous Center, on north Broad.)
But wherever they build, if at all, it should be part of a larger planning initiative. The arena itself will not itself bring about a neighborhood transformation.
*- it is a damn shame what the La Salle basketball team has been reduced to. When I went there in the late 1980s / early 1990s, they played at the Palestra and then the Civic Center. The Palestra is legendary, and the Civic Center was a beautiful arena. Ironically, I was on the team that built what replaced the Civic Center - the Perelman Center for Advanced Medicine.