The level cap is left on and the ilvl sync'd to the highest point for that expansion (which is 130 for the crystal tower stuff) because otherwise people would literally 1 shot everything. The bosses would not even have time to do an auto attack. There is a difference between "easier" and a walk in the park.
I'm just responding to the point about how things are "intended" to get easier and easier over time. This just seems like the next natural progression step.

Bottom line is that if things remain as they are, the 60 and 70 raids will *never* become as easy as the 50 ones. They simply aren't currently designed to be that way. The 60s and 70s we cannot overgear as much as we can for LotA/ST (technically we can, but it makes far less of a difference as being i130 in LotA/ST does), pretty much everything has proportionally higher HP and takes longer to kill, there's far more mechanics that have a reasonable chance of killing people and slowing the raid down, etc.