Mushy brakes 4 life...

Replaced 100 or more,bench bled every one. As per manufacturers instructions.
I still dont think drum is the issue.
Crank brakes up tight with adjusters and try pedal. Zero clearance should mean hard pedal.
Backing plate rubbing in only one spot,plates bent?

Soft pedal,maybe reverse bleeding. Pressure bleed from each wheel pushing fluid up to master. I have never had to do this,especially on domestic. 75%are usually successful just gravity bleeding.