If something is serviceable and reasonably attractive, then I think it should be used, regardless of age; unless it's very fragile, or extremely valuable.
Such is the case with my nice old Maple handled, and carved, bread knife. Made by the highly regarded Joseph Rodgers & Sons of Sheffield in around 1920, it still cuts as well as ever, and is a pleasure to use.
OK, a nasty serrated, white plastic handled, stainless steel blade might do the job, but working with a tool that's been in use since George V was on the throne (1910-1936) is a true pleasure.
I can't recall its history, but it must have cut an awful lot of bread; and hopefully will continue to do so.
p.s. I was watching TV's 'Flog it' recently where someone was selling a sliver tea set. The Teapot was marked JR and had the star and cross mark, used by Rodgers since 1764; well within the age of the Teapot. The expert attributed it to someone completely different. As you might imagine, I shouted expletives at the screen!