I try to undestand how to build an XOR gate using discrete transistors. I checked this question with an extensive answer
Howerver the xor gate there and also on Wikipedia seems needlessly complicated. I simulated the following circuit in Logisim and it seems to work. It is based on the idea that input B switches between A and not A.
Since I did not find this circuit documented as an XOR implementation, I expect it is not feasible. Please explain why.