I would not call it a easy way for Real Madrid. Though historically they have the highest number of titles but they are struggling this season at home league. They have even lost to Atletico Madrid in home ground. La Liga teams had been dominant in most of Champions League but considering their three way struggle and below average performance, this time PSG or Liverpool could be a better candidate. It's sad to see those two again playing each other in round of 16. Bayern Munich would be another contender and they have got an easier opponent who they are used to winning.
I also see that Real Madrid’s condition this season is a little different from before, but sometimes it is not quite accurate when comparing Real Madrid’s performance in La Liga with Real Madrid’s performance in the Champions League. Because even though Real Madrid were beaten by Atletico Madrid at home, it doesn’t mean that Real Madrid have become really bad this season because Madrid are a team that is able to make a comeback when the season is running like now.
In addition, it seems that PSG will find it difficult to beat Liverpool this season because Liverpool has a much better condition than the previous season, and moreover, PSG has also failed very often in the Champions League so that the team has not had a single Champions League trophy while competing in the Champions League.