Curse of the Guardian(s) (Debuff)

Recently when playing minecraft i noticed how easy it is to travel through ocean monument ever since 1.13,

I was thinking the Elder Gaurdians should have a new debuff with a name like 'Curse of the gaurdian(s)' and the effect should slow down your swimming speed, as well as slowing down your mining speed. 

This could also have an added debuff where you lose your breath faster, especially since turtle helmets are a thing. I do believe this might be a bit much for a debuff but it would balance out how fast you can swim through monuments currently and avoid all damage.

Elder gaurdians could also have a chance of dropping Heart of the sea, or nautilus shells?