If a show closes it could be because it's not making enough money, renovations, or it was a limited run. However a lot of people can comment on that through social media in a way that is rude and unkind.
Actors and the people who run the show's social can see these comments. While there are shows I was not the biggest fan of that are closing or have closed, it is not right to go out of one's way to say that the show deserved it, even if that is your opinion.
Shows that come to Broadway share their stories with audience at times a week for several months or several years. For many people they remain a favorite show, and for others they may not have loved it. But, every show has made an impact on Broadway and what can be done in a musical or a play.
And though they close, they open up a theater for something new to come in that may also push the envelope or do something we never thought could be done on the stage.