It would be very naive if Madrid did that because in the end we also cannot assume that Bayern is an ordinary club, especially with the release of the Bundesliga trophy at this time, so the goal is the Champions League because it is the only way for Bayern to save their face so surely they will try as hard as possible to get good results so it is wrong if Madrid considers Bayern underestimated in the semi-finals this time.
But for now with Madrid winning against Manchester City some time ago, their probability has increased and they are the favorites in this competition.
I personally still feel that until now Madrid is the favorite for the Champions League and indeed I feel that now is the place for Madrid to get their 15th trophy.
They have always been one of the most dominant team in the UCL in recent years so caution would be employed while playing them no matter their form.
Madrid can be considered a favored child in UCL
No matter their form
They always are the likeliest to win the trophy and who ever manages to win them has already won the UCL.
If you look at the statistics, maybe Madrid is far superior to Munich, but the previous season and the current season are clearly very different in terms of strength, that's why it's hard to underestimate one of them, but I'm happy if this match is full of surprises, I'll bet on both of them scoring goals and Madrid will win the match in the first and second legs, so far I see that Madrid is playing quite better than last season where they were able to balance Manchester City's game some time ago and finally got rid of them to make Madrid qualify for the UCL semi-finals this season, It seems that it might be true that they want to add to their 15th UCL title collection.