In 2014, they finished third in the league and in the CL, they narrowly edged Dortmund 3/2 on aggregate having to survive a second leg Juventus style. They were lucky against Bayern in the first leg producing admittedly a brilliant performance in the second. In the final, they were saved again by a last minute header having looked impotent throughout the game.
In 2016, They were about 10 points behind Barcelona late in the season before finishing a respectable second (yet again in the league). In the CL, they lost 2/0 to the mighty Wolfsburg before a Ronaldo hatrick saved them only go on to produce one of the most limp semi final performances against an even limper City going on to win a very even final on penalties.
I am not disputing their quality as I stated before, nobody can deal with game on the edge moments like they can. They always seem to find what's needed. But to suggest they were a brilliant team bar 2017 is overlooking some serious flaws. Unless of course we differ greatly on what constitutes a brilliant team.