The only advantage of Bayern Munich signing Ronaldo is that they will generate more money from the sale of jerseys. Signing Ronaldo will also require lots of money for Bayern Munich.
I don't think Bayern Munich need that, Bayern prefer to strengthen the line-up, they don't look like they are short on funds. Bayern need players who can make the difference and cover the gap left by Lewandowski, and Cristiano Ronaldo is still less effective for Bayern's needs.
I'm pretty sure of the signing of Sadio Mane but to maximize their desire, Bayern need more than what they have at the moment to partner Sadio Mane up front.
Bayern's achievements in the Bundesliga further reinforce the notion that they need new players up front
Agree with what you said, even though Ronaldo is currently still a very good option, especially in productivity scoring goals but of course they can still look for potential young players rather than expecting someone who is quite phenomenal like Ronaldo but his career will definitely end in a few more years.
They are also not ambitious in bringing in Ronaldo so there is no reason for those with the financial condition to do this.