Really? I've never seen Twighlight Zone or The Prisoner included in a list of unreleasable Blu-Ray shows. If anything they are the shows that people said COULD be released on Blu-Ray. The shows that are nearly unreleasable in HD are the shows from the 80s-00s. Those are the shows that were worked on in video and have no hope of higher resolution without reverting to the originally shot negatives and re-editing the entire episode.
I've seen both. I also saw Trek TOS listed as unreleasable unless they farted around with the SFX which they did for TOS/R. And that show well predated the whole edit-on-video thing (and of course TOS ended up on Blu-Ray in its more-or-less original state, too). Anyway, the point remains moot so long as Blu-Ray remains backwards compatible with DVD. They're going to have to figure out a workaround (that doesn't involve remaking everything) by the time either Blu-Ray standards change and backwards compatibility is no longer allowed (sort of like what happened with PlayStation when they moved up the models, and also things like the move to Intel Core Duo Macs making it impossible to use most software from OS9 and earlier), or a new format comes along that is only HD (or, worse, only 3-D) compatible. They must come up with something, otherwise they're going to lose billions of dollars investment as 60 years worth of TV production becomes "lost culture".
As I say, the key remains whether or not the shot-on-video TZ episodes will be included in the Blu-Ray edition. If that happens, then IMO it opens the door for a lot of video-related material to be released in high-def, from old-school Doctor Who to All in the Family ...