First up the champions of Latvia, then the champions of Iceland, next up the champions of Austria in the quarter final.....
Save for the odd side in the Champions League you are playing quality opposition from the best leagues in Europe as soon as you hit the knockout rounds and even before that the group could be the end of you, see United and Dortmund last year and Chelsea City this year.
Pretty sure Latvian Champions didn't really feature in it so that's a little disingenuous. Moreover, the standard of football across Europe was far more even and less centralised in big economies and within those big economic countries, less centralised in a few power-brokering teams. So in fact, the European Cup back then was a far more even ground for competition, at a different time in football, with less money in it, less technology, less travel and so on. It's pretty pointless to compare all in all. About the most sensible thing you can say is that it is difficult to win that trophy at any stage*, and anyone who has won two, no matter how long it took them to win them, did pretty well.
*Except for Madrid's first five, which were obviously a complete shit-show.