Without wanting to give Liverpool too much credit, I believe that they started this season with 'only' the 5th highest wage bill in the Premier League, comfortably behind City, Utd, Arsenal and Chelsea in that department.
Winning a title despite not having a top 4 wage bill in that season (at least during the first half or so of it) would surely be a rare occurrence - clubs' wage bills, far more than their spending on transfer fees, are usually the biggest indicator / correlation of where they'll finish. Other than Leicester's miracle triumph in 2015/2016, I can't think of other examples of that in the Premier League era.
I'm assuming that we had the largest wage bill in the league in 1994/1995, and that Chelsea definitely had a top 4 wage bill in both 2014/2015 and 2016/2017, in addition to a top 1 / top 2 wage bill in 2004/2005, 2005/2006 and 2009/2010.