TCP_MAXSEG object to change the size of the largest TCP data segment MSS. By setting, data can be transmitted through user-defined MSS.
However, MSDN clearly points out that TCP_MAXSEG setting is not supported, that is to say, MSS setting cannot be realized in this way in Windows environment.
As we all know, in general, the value of MSS is determined by both parties through negotiation when TCP connection is established, and it is generally unnecessary to set it artificially. Maybe that's why Windows doesn't support TCP_MAXSEG.