Salāmun 'Alaykum,
We have already learned that we curse ourselves and those around us when we use this form of greeting:
As-Salāmu 'Alaykum (السلام عليكم) = (The way to) As-Salām (i.e. Allah) is upon you!

While studying this concept, one thing came to my mind that seems to be closely related. "Muslims" very often say "'Alayhi As-Salām" after mentioning a prophet:
'Alayhi As-Salām (عليه السلام) = (Only?) Upon him is (the way to) As-Salām (i.e. Allah)!

This is another statement which possibly explains our state in the last 1400 years. The people who say this are literaly expressing that these Nabiyoon should be intermediaries to them in order to get to As-Salām. They are propagating and expressing their wish to stay in the old "Torah System" where Nabiyoon were needed.

The "Muslims" who are saying such things are surely influenced by the Qareen (of the Nabiyoon?) who want the old system and the crooked way.
I would suggest refraining from using this curse in case anyone of you does this out of habit.

And one more thing: Did you notice the change of the word order? Is this an application of "Hysteron Proteron"? Why do they not say "As-Salāmu 'Alayhi". It seems like this expression is attributing exclusivity to the person in being the only intermediary to reach As-Salām. Imagine many people talking about various Nabiyoon and everyone says "Alayhi As-Salām" after it. It seems like they are fighting about who the exclusive intermediary is.
But I could be completely wrong due to my weak Arabic skills.