Some people will start with Estrogen blockers for a month or two. They do this to completely kill their estrogen, end their cycle etc. so thtat when T kicks in.. it's able to start working immediately and not have to fight estrogen first (you can also start on a lower dose then).
The issues with taking estrogen blockers permanently is that with no T being supplemented and low levels of estrogen you may/wille ventually face issues that arise from having low hormone levels.
But then again if you have naturally high T levels.. we're talking high, you could just go for the estrogen blockers.