Well you could argue that the year the won it, most of the big teams in Europe were in transition. So in some ways it was like Leicester winning the league when all the big teams had horseshite managers - Van Gaal at Utd, Pellegrini at City, Brendan Rodgers started the season at Liverpool and had had a horror summer transfer window, Jose in his 2nd stint at Chelsea and losing the dressing room in one of the first games of the season for childishly and disgracefully verbally abusing a top female doctor in front of the whole stadium.
Porto's road to the Champions League title in 2004 was Lyon in the quarters, Deportivo in the semi's and Monaco in the final - about as handy a run that a team could ever dream of. And who could ever forget the cock-up of all cock-ups from the inexperienced Tim Howard in the last minute of the game against Porto, in the first round knock out stage, to giftwrap a victory for Jose? Would Schmeichel or Van de Saar have made such an error? No chance.
I don't think Jose's Porto team were any better than the Monaco team of Mbappe of 2016 who got to the final, or the Ajax team of 2018 with De Jong and De Ligt that got to the CL Semi's, but when you study the teams they faced and the luck along the way, one could argue that Porto's luck that year was on a par with Leicester in 2015/2016. It was a brilliant achievement from Jose, but he's been overrated ever since, in the same way Van Gaal's ability as a manager were greatly overrated from winning the CL with an Ajaz team boasting the greatest collection of wonder kids the game has probably ever seen. Ranieiri's talent as a manager also being vastly overrated for a short period of time after Leicester win.