Nor when West Ham drew with Liverpool and United away.
As repetitive as this argument gets, I doubt the Copa Del Ray revives this argument as you're trying to with the FA cup
Well Liverpool beat Watford, Stoke and Middlesbrough heavily too and all in last two months. Chelsea thrashed United, Everton and Leicester in the space of few weeks, Arsenal battered West Ham and Sunderland - these results happen in Premier League too.
Well that did not happen either when Barcelona dropped points to Celta, Malaga and Sociedad in the last two months, or when Atletico dropped points to a lot of teams, and both Barcelona and Atletico are a fair bit better than PL teams.
Upsets happen everywhere, they are less common in La Liga because Madrid and Barcelona are excellent.
Back in 2004-2008 they were losing games left, right and centre and teams like Valencia, Villarreal and Sevilla were in title races but nobody claimed then that La Liga is head and shoulders above Premier League because of its competitiveness, well because Premier League teams were killing it in Europe and it was common opinion that PL was the best. Even though it was strongly dominated by runaway champions Arsenal in 2004 and Chelsea in 2005 and 2006, and then only had two horse races between Chelsea and United before City appeared (with the odd Liverpool 2009 run).
It wasn't very competitive but it was VERY good and teams proves it in Europe yet now when the roles have turned, it is somehow more important that many teams are fighting for the league and European performances can be written off because, well, PL teams cannot compete there because they 1) don't care, 2) are too tired from exhausting PL games.