The essence of materialism is that ones perceptions reflect a real world.
Nope, materialism is based on evidence. This gives the perception (whatever that is) the correct viewpoint to assess an
objective world, that is, that which is there whether you are there to experience it or not.
There is no "unreal" world.
There's a problem in that it also has to be accepted that perceptions are sometimes incorrect, and don't reflect reality.
I sorta see where this is going, however reality doesn't change, even with an incorrect perception.
Just because one might think it is so, does not make it so.
Figuring out whose perceptions are valid and whose should be discarded is effectively done on the basis of popular vote.
Only amongst some of the population, the more uneducated perhaps.
A lot of people once thought the world was flat and had corners, it wasn't just a vote that convinced them it was round.
The independant evidence did most of the work.
Even if that evidence is rejected, as in a lot of theological thought sometimes, that don't make it so..
After all, if our perception told us the world is flat, and it became so, what a mess that would create........