To win the EL this season, we'll have to play 21 games, I think? As opposed to 12 in '72 and '84. At least they've cut down on the League Cup games.
I personally enjoy these games--I like seeing players who aren't normally in the rotation, and I enjoy watching European teams I don't get to watch normally. But it's definitely difficult for PL teams, most of which are also sending lots of players away to these useless international friendlies that seem to be every three weeks now. It's hard for clubs (not so much managers, but club hierarchies) to complain too much about fixture congestion when, in a normal season, they've got players flying all around the US or Asia in August.