Microsoft has a high share in this area but enterprise security is generally a very competivite market. Microsoft may even move into #1 position as a fallout from this debacle becasue the market share between them and the #1 CS is very small (that does not mean people actually buy more Ms btw... if that needs to be said ;)
This is not neccesarily a good thing for MSFT as it will 100% trigger regulator rage in the EU.
https://www.statista.com/statistics/917405/worldwide-enterpr...