Altar-girls 2 (no electric boogaloo)

It appears that there is far more to the restriction of girls as altar servers that I am not grasping. 

I mean, if there are young people who desire to serve God, one would think that is the sort of behaviour one would wish to encourage.

If we are to believe Galatians 3, gender is no bar within the people of God as we are all made one in Christ. 

If we are to apply the Golden Rule, why would anyone wish to exclude another from Christ's table, from participation in mass or in any form of worship?

And what about Christ's own words?

"And whoever receives one such child in My name receives Me; but whoever causes one of these little ones who believe in Me to stumble, it would be better for him to have a heavy millstone hung around his neck, and to be drowned in the depth of the sea." (Mat. 18:5-6)

I mean...I realise that pre-V2 RC didn't allow the laity to read the scriptures, but I thought that V2 opened it up, not prevented the clergy from reading them too.

Oy gevalt!