Yes, I also think that if Barcelona make some mistakes, both clubs from Madrid will be able to take advantage of it... Besides, Atletico Madrid only have matches left in La Liga, not counting the cup, where they will meet Barcelona again... Real Madrid and Barcelona still remain in the UCL, making their schedules more difficult than Atletico's... The gap in the standings isn't very big, so the chances aren't lost for anyone yet...
All three still have the same chance in terms of competing for the title in La Liga, while for the Copa Del Rey we still have to see who among them makes it to the final because all three are still there and have not been eliminated. I also think that Atletico Madrid are actually a little more relieved in making player rotations because Atletico have been eliminated from the Champions League, while Barcelona and Real Madrid still have to keep their main players from getting injured in the current conditions because now is a crucial time for both of them.
The emination of Atletico Madrid for the champions league was quit a moving effort to them and it might them some edge in terms of player rotation say you have said without them adding huge amounts of pressure of European competition which this will make them fouce more on some domestic tournaments, meanwhile if we are saying Real Madrid and Barcelona much have to balance their chances in the La Liga and copa del with the demands of the champions league.
If we check closely the heat is heating up between Barcelona and Real Madrid and Atletico Madrid are having an contention, as you mentioned earlier the three teams are having equal opportunities to win the tournament and making the remaining games crucial,
The last time I have checked Barcelona is the most successful club in the competition history with 31 titles and while teams Real Madrid are following closely as then also are having 20 titles while as for Atletico Madrid are in the third place for have 10 titles if we check since all the three teams are still in running it will kind of hard to predict who really make it to the finals.