What did Winston mean by this in 1984? What lead him to this realization? Quote below. "The Proles had stayed human."

The proles maintained a humanity much like our very own.
However, it was a humanity that experienced emotion without thinking too deeply. The
proles were allow to act much differently than Party members and kept more of the
rituals that we keep today (sex was for pleasure and in relationship, not like within
the Party as a duty to the Party).

The Party was ever
watched and guarded. The proles were more able to roam the streets. But, all the same,
the proles were controlled. This seems a little ironic to me to even call them human.
They were manipulated in their thought and allowed to commit greater moral sin than
Party members, so it would seem they were more free. But they weren't. They were removed
from thinking about the Party and were well unaware of what it was doing. I'm not sure
if that really can be called human. One of the great advantages I find in this life is
the ability to think and analyze this world around me. That was taken from them. I think
Winston says this quote to make us think about what it does indeed mean to be
human.