Every software developer knows that removing (unused) code makes software less vulnerable because it reduces the attack surface. That's a fact. Strange that some people defend extra features (extra code) even if they are not using them...
Even if i don't use that feature, someone else does and there's developer willing to implement and maintain it. But if no one willing to maintain it, i agree it's time to remove it gradually (starting from deprecation warning to actual removal after some time).