OK, I just tried a test...
I am running Windows 10, and using Firefox 55.0.3 as my browser.
I unchecked the box in my Settings. I went to a thread and noticed that the signatures still showed. So I logged out of the forum and cleared the browser cache. I closed the browser, then opened a new session and logged back in to the forum. Most signatures no longer appear, but in Bish's post above, for example, I see the badges he has in his signature.
I tried accessing the forum next, using Chrome v61.0.3163.100. I cleared the browser cache first, then launched a new session, accessed the forum, and got the same result. Most signatures are hidden, but I still see badges in some members' posts.
That's why I suggested that you post some additional technical info-browser, operating system, also, are you on a mobile device or on a PC/laptop, etc. That will help the support people troubleshoot the problem and fix it.