Dependency of Collector current in common base transistor(active region)
You are discussing TWO DIFFERENT REGIONS of operation.
Get an I_V plot for the bipolar device.
The Saturation is at far_left, with little Vce to cause &quot;collection&quot; to succeed.
The region where Ic ~ Ie uses substantial Vce, and &quot;collection&quot; of &quot;emitter&quot; will be nearly 100%.