1984 Van 2wd weak brakes

[Toyovan]

Quick back story to my van. I purchased my van back in 2021. First thing I noticed is how bad the brakes felt. The first 3/4 of pedal travel goes down easily with no resistance and makes a "decompression noise" the last 1/4 is when the braking starts but even then it doesn't feel convincing. The van feels more like it's "slowing down" vs "stopping" if that makes sense. Fast forward 3 years later over time I have changed front rotors, pads, calipers, rear shoes, drums and cylinders. Every brake hose and brake master cylinder. I have bled the system dozen of times, bench bled the master cylinder. There's no air in the system. I even bled the valve in the bottom middle. I have done the test to see if the brake booster is good and it checks out (i know bad brake booster means hard pedal) as it's the only brake component I have not changed. I have adjusted the rear shoes. System has no leaks. The brakes feel absolutely the SAME from the first time I drove it before changing every part I have. Are the brakes for this van not that good to begin and I'm just overreacting or is there something else I'm missing?