I think you're right to an extent, any owner that's mostly trying to run a club like a business (even an ambitious one) is never going to be able to compete with City (though they've been quite restrained recently, by their standards anyway).
But I don't think building a team specifically to just get top four is smart either though, it limits how much the brand can grow. You need fans to know the team will or can at least challenge for the big trophies. Constantly yoyoing from 6th to 3rd isn't going to do much to grow the global fan base. If you can challenge most years and then and throw in the odd league title or CL trophy then you'll reap the benefits, you don't have to go to City's level where not winning the league is a failure.