I have bad news for you, Premier League dominance will be far longer and more boring.
I'm not sure that we'll see domination by one league. There will be seasons like 2019, when teams from 1 league will do (much) better than the others. We might get two CL finalists from the same league; a CL and EL winner from the same league and so on, but I don't expect domination like the La Liga one from 2009 to 2018.
I think so because the La Liga domination had a lot to do with the best years of Messi and Ronaldo. They are possibly the 2 all-time best players and they happened to play at the same time in the same country. They didn't just make their own teams better, but somehow the whole league became better. I am not underestimating Xavi, Iniesta, Neymar, Modric, Ramos, Luis Suarez, Bale, Atletico Madrid and Sevilla here. They all contributed a lot to the success of La Liga. Still, most of it was about Messi and Ronaldo.
The possibility for another Messi-Ronaldo pair in the near future is slim to none. That makes the possibility of a league brutally dominating all the other leagues for more than a season or two just as slim.
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When's the last time no Spanish team made the quarters?
It's been a really long while hasn't it
2004/05. Before that, in 1992-93 (first CL season) there were no Spanish teams in the last 8.
That's 2 times out of 28.
For comparison:
Italy 5/28
Germany 5/28
England 6/28
France 10/28