Being a Philly native, I used to wonder this myself, but I think I have it mostly figured out.
1) Philly suburbs have their own stations. In most places, the suburbs make Hot AC work. Philadelphia, however, has a bunch of smaller markets right next to it. Bucks County Hot AC listeners listen to WPST, which is a very adult-leaning CHR right now. Chester County listens to WSTW, which has been an adult CHR forever. The South Jersey suburbs have their own Hot AC in Sojo 104.9.
2) Philly never had a Hot AC tradition. There have been tons of attempts at Hot AC over the years. Every time Philly gets a successful Hot AC, something happens to screw it up. Lets go back to 1992, when the Hot AC format was first getting started:
- CHR Eagle 106 was the first to give it a shot with their "No Rap, No Hard Stuff" position. The station had a great morning show and was getting decent ratings but the owners thought it was too expensive and pulled the plug. It was a top 10 station at the end of its run.
- After Eagle's demise, an AC station in town switched to Hot AC as "Z100". New York's Z100 wasn't happy about this and sued. Rather than face the lawsuit, this station became Y100. Y100 did OK ratings-wise, and ended up just outside of the top 10 stations, but this was when Alternative was becoming big, so Y100 jumped on that bandwagon and the Hot AC format was dead again.
- The next attempt was from perennial loser Star 104.5. Star had bounced around from one format to the next, trying Bright AC (their most successful format), Rhythmic AC, CHR, before finally settling on a Hot AC format in 1996. Problem was no one knew what to expect from "Star" anymore. It was a brand name that meant nothing to Philadelphians. The Hot AC format lasted a few years and eventually flipped to Rock AC (not Modern AC) as "Alice 104.5". "Alice" then evolved back to Hot AC for a short time in 2001-02, but again, Philadelphia just didn't take to it. Probably had a lot to do with the station's lack of consistency. No one knew what to expect out of it. If Star had just evolved from Bright AC to Hot AC around 1995 or so, I think it would have been a very successful station even to this day.
- Then there was 95.7, another perennial loser frequency in Philadelphia. They started Modern AC as Max 95.7 in 1997, but faced low ratings because they were squeezed by Hot AC Star 104.5 and female-leaning Alternative Y100. Their ratings were starting to pick up in 1999, though still very close to the bottom, when the owners pulled the plug to try Jammin' Oldies. 95.7 did Modern AC again in 2001, as Mix 95.7 this time, again facing a lot of competition from Hot AC Alice 104.5 and 80's station 96.5 The Point. Again they were unable to get ratings and they flipped to a Rhythmic-heavy Hot AC (a la KBIG) and then back to Hot AC again after 96.5 flipped Rhythmic. Eventually they became Ben-FM, which is the closest thing Philly has to a Hot AC right now.
- 96.5 The Point started out as an 80's station, but evolved to Hot AC towards the end of its run. Much like 95.7 and 104.5, it was a station that was inconsistent and not given any time to work out before moving on to the next thing.
The point of this long, long story is that every attempt to do Hot AC was ruined either by inconsistency, incompetence, too much competition, or just not giving the format time to succeed. The interesting thing is that Philly had two Hot ACs in the late 90's (Star and Max) and also in the early 2000s (Mix and Alice, then Mix and the Point). All of the stations had lousy ratings though, and as I pointed out before, the strong suburban stations didn't make it any easier.
3) The mid-Atlantic region in general is a bad place for Hot AC. It's not like the South or Midwest where there's still a backlash against rap. Even successful stations like PLJ and Mix 106.5 don't set the ratings world on fire. They bring in money because they're heritage stations and they hit the right suburban demographics. As I just pointed out in 1) and 2), Philly has a tough time with those factors.
As long as Ben-FM is doing well, I don't think Philly will see a new Hot AC anytime soon. If you look at their
top 10 on yes.com, it is basically substituting for a Hot AC in the market, although it is extremely conservative on new music. It is able to get ratings because it also fills the Adult Hits void and the void for a second AC station. Philly listeners are content listening to 95.7 or tuning to the suburban stations.