I can't believe no one's figured it out yet. It's so simple
Paladins are holy knights correct? Lay on Hands is laying your hands on someone right?
By using LoH on ourselves we've been sinning. God is angry that we've been touching ourselves all these years.
In the beginning using we didn't use LoH much because it was bad for us. After a few years and some things changed we began touching ourselves more frequently. and now god is punishing us.
This explains the Sacred Shield nerf too. God will be shielding us less frequently now. If we keep it up eventually we'll lose Divine shield, divine protection, and even the use of the Holy Light. We'll have to make our living by selling crack on the street.
To fix this we must perform ancient catholic rituals. We have to go to the cathedral of light in stormwind, target the altar boy, and.... ok i'll stop now.