Don't know how many teams have only made the playoffs once in that time, but there are only four teams in the AFC with a longer playoff win drought than the Steelers. Those teams are Miami, Las Vegas, New York Jets and Denver Broncos. The other 11 AFC teams all have at least one playoff win since the Steelers last playoff win. That puts Steelers in the bottom 35% of AFC teams last playoff win.
Your statement that the team hasn't had the horses to make a serious run doesn't say a lot for Tomlin's ability to build a contender does it? This year he has his choice of quarterback, his choice of OC, his choice of DC, his choice of assistants and yet it's the same story it has been for the last 7-8 years - as soon as they play a good team in a game that matters they fold like a cheap suit with the offence struggling in the first quarter and the defence unable to make a stop. At this stage I can't see Tomlin building a team that is a real contender. He is a good coach, but to be better than good he needs a winning playoff record and better than 1 and done in 7 out of 11 playoff appearances. To be great or elite he at least needs more Super Bowl appearances, if not another Super Bowl win.