Visited the Louvre 12 years ago, and even back then it was bad. You had to fight your way to the front to even get a glimpse of the painting. And indeed, it is disappointing and an overall unpleasant experience. I am not ashamed to say that I have never even remotely understood the hype around this particular painting. Just compare it with Da Vinci's Madonna of the Yarnwinder [0] - I find it to be vastly superior to the Mona Lisa.
If you visit the Louvre, just stay out of the room the Mona Lisa is in.
I think there's value in it being a disappointing experience as a learning opportunity. Might encourage people to think about what makes something famous, what draws crowds, hype and substance, etc. And hopefully people spread out afterwards and see surrounding pieces (I liked the Charles Le Brun pieces that were, at some point, in a large gallery near the Mona Lisa crowds).
If you visit the Louvre, just stay out of the room the Mona Lisa is in.
[0] https://upload.wikimedia.org/wikipedia/commons/thumb/7/73/Ma...