in Bangladesh it’s common to remove Muhammad from a deceased person’s name, for example if someone was named Muhammad Ali or Muhammad Firoj Ahmed, after death people refer to them or write down their name as late Ali or late Firoj Ahmed, they claim that Muhammad is only valid for the living human being.
So, Sheikh is this practice justified or is it baseless.
This is totally baseless and an innovation and it is part of most likely the false and deviant belief of those cults and sects that believe that prophet Muhammad صَلَّى ٱللَّٰهُ عَلَيْهِ وَسَلَّمَ