if AIO is non abbrasive cleaner, wouldnt it be better to just use a clay bar and skip the paint cleaner? what am i missing?

Two different cleaners for two different types of blemishes. They don't compete with each other, hence your confusion.
AIO is a chemical cleaner and a bit of a sealant, dealing with oxidation, surface stains like asphalt, tar, etc.
Clay sticks to physical imperfections that imbed themselves into the paint/clear surface. The clay grabs them and physically pulls them out.
That's the difference, so they enhance each other.
-John C.

Two different cleaners for two different types of blemishes. They don't compete with each other, hence your confusion.
AIO is a chemical cleaner and a bit of a sealant, dealing with oxidation, surface stains like asphalt, tar, etc.
Clay sticks to physical imperfections that imbed themselves into the paint/clear surface. The clay grabs them and physically pulls them out.
That's the difference, so they enhance each other.
-John C.

Couldn't say it any better ;)

so would you say a cleaner is absolutly necesary if you clayed and then were about to polish with a pc?

so would you say a cleaner is absolutly necesary if you clayed and then were about to polish with a pc?
No...polish first and then use AIO as a pre-sealant for the SG

so would you say a cleaner is absolutly necesary if you clayed and then were about to polish with a pc?

It's important to make a clean base for your sealant to bond to. For this reason AIO or your paint cleaner of choice is used to prep the paint.