Let's keep it simple. Jehovah was not God's name it is a made up name that was first published by a Catholic Monk in I think the 12th century maybe the 13th. The WTBTS acknowledges this.
If Jesus was down with Father or Lord....... leave it be. Good enough for Jesus....... good enough for me.
I think that there is a case to be made for not calling God by a man made name.
There is also a level of disrespect at play. If I am walking down a street in my small city where everyone just about knows everyone else and I hear "Hey Gio! Giordano !" I am going to respond...however if some one calls me John or Jolly Rodger then I know they don't mean me. So I don't interact.
Now let's move this to a different place. Heaven is God's home. Did you ever think how pissed off God would be if your praying to a God with a made up name like...Jehovah? Is that one of the reasons God doesn't interact?
Now you've got the reason prayers are not answered. There's no one home and there's no answering service.
A final thought...... Christians were supposed to be Witnesses For Jesus.......... says so some 20 times plus in the New Testament...witness of Jehovah is mentioned once in the Old Testament .
The Society really screwed up when they named their shinny new religion...... Jehovah's Witnesses. To this day people are confused by that name. We explained out in service that Jehovah is the name of our God...before the door is slammed in our face.