I don't understand all the hubbub. If I understand correctly, we have a maintainer of a key package who's lagging far behind upstream and--even worse--not communicating with the community. He's ignoring discussion for *years*. This is simply uncooperative, and perhaps territorial as well.
These attitudes don't belong in a project like Debian. The decision to replace him as maintainer should be obvious and straightforward. The issue of stepping on toes has long since passed.
What's the concern? That he'll be offended? So what? The entire Debian project should be offended by his lack of concern and cooperation. Afraid he'll stop maintaining other packages? So what? Others can take over, just like this one--he's replaceable.
The Debian tradition of respecting each developer's prerogative over his packages is fine--but we're not talking about neverball here.
His silence speaks volumes. And that's the real issue: as much as technical issues ought to trump social ones, Debian is not a one-man project. Participating in such a group carries responsibilities, perhaps chief of which is to cooperate and communicate. Refusal to do so should be unacceptable and should be ample grounds for uncontested replacement--especially when teams of volunteers are waiting in the wings.
What's the problem? Just fix it.
(If I misunderstood something and have unfairly criticized anyone, please correct and forgive me.)