Sure, but the same principles apply to EVERY hero. *This isn't a learning curve unique to Pharah, and she's not particularly difficult to figure out in this respect, compared to other flankers. *Like I said; you can do some crazy stuff with Soldier 76 about getting to spots that aren't expected, but that involves learning to use his rockets to boost your jump and such. *Reaper needs to know where drop zones are, while Pharah IS her drop zone.
Which isn't saying she's "easy". *I'm just taking issue with the idea that she takes way more skill than Roadhog. *A good Roadhog is ALSO gonna be flanking and getting at people from unusual angles, and his fat ass has no mobility advantages.
It depends on team comp/awareness. If they're watching for flanking, you'll be dead in seconds. If they don't have long-distance direct damage, which basically means Widowmaker, McCree, and Soldier 76 (Ana too, but if your team's playing right, she's too busy to focus you), she's almost unassailable at long range. And even there, McCree and Soldier 76 have issues with damage falloff and, in Soldier 76's case, bloom. This can make it difficult to take her out at those distances, even with those heroes (and Widowmaker's not really great outside of this one thing, for the most part), while she rains down explosive death. What she loses in accuracy she gains in carpet bombing with impunity and never dying, especially if her team has an Ana or Mercy keeping her topped up (Zenyatta works too, but slower).There's so many tricks a Pharah can use that I don't see many others use at all. But then again, I haven't really been up against exceptional Pharah's myself. It's not just throwing missiles and hope for the best. Long-range Pharah = Bad Pharah. Close combat ambush Pharah is what you need to fear. (Unless you spam missiles as the defending team, like a Junkrat spams a certain doorway to prevent them from going in, but those are only a few situations).
At high comps, people will swap and do their best to wreck this anyway, but that happens regardless of what you're picking.