1 EPL club has won the UCL since then (Liverpool last year). I thought I was being generous by letting the EPL count its wins in the last 20 years, and not just the last 7 or so.
Also, I'm not sure how Real Madrid and Barcelona are losing ground to the EPL. They have won 5 of the last 6 Champions League combined. Atletico Madrid was also a finalist twice during that span. Last year was an outlier until proven otherwise, like the year Porto and Monaco met in the Final.
With Liverpool already knocked out of this year's tournament, the odds are pretty good that a non-EPL team will win again this year, and it could be a La Liga side (Atletico actually look like they have as good a shot as anyone).