Yes very true, but because the M1 chip is a SystemOnChip(SoC), things like the RAM will be very difficult to change by users, but Apple could have made room to change the ssd’s unless it will affect the MacBook. My theory is because the MacBook uses the high performance ssd as a swap partition and also a storage partition (you can check this story by Mark Ellis, he reviewed his own M1 ssd and the data read and written was high, you can check his story here), removing the high performance ssd, and putting in high capacity but lower performance ssd will affect the M1 performance.