Why should anyone be forced to change there username unless they request it. Unless of cause its rude or offensive

It does not take much to reread the big bold red writing on the left if your not 100% sure of who it is. I often go to a forum were theres a few usernames similar. For example ones called 'the hated guy' the other is 'the other hated guy' both have similar writing styles too. Same forum also have similar ones were people use first names so we have a 'jeff' , a 'jeffb' , and 'jeffd' etc. You just have to get use to reading who posted what by looking at the username, avatar, sig.