All of this has to be created again, and that would in no way be the original show anymore.
Well yes, that's self-evident. It was designed to be seen on a small 525 line CRT television in very much standard definition.
Any attempts to make it available in HD will mean it is no longer the "original" version.
Welll, you're a little off here. Just making a show or movie HD doesn't mean it isn't the original. For instance, the original Star Trek is in complete edited form on film. The high-definition you see on the remastered blu-rays is actually already there on the film. In fact even more detail than that is on the film. The remastered Star Trek is, therefore, the same thing as the original. There is no "original" version vs. "remastered" version. The "original" version is what's right there on film. In order to make it HD, all they had to do was make a new transfer and show more of the detail that's already there on the film.
What makes TNG different is that the episodes are on videotape, meaning there is no extra detail to show. Whereas TOS episodes included tons of extra details you couldn't see because of the limitations of your TV set, there is no more detail to the TNG picture. What you see now is all the detail that exists. So to make the show HD, the episodes have to be reassembled into new edits from the original film elements.
In other words, remastering the original Star Trek preserved
the original. "Remastering" TNG would be more like remaking the series.
But the idea that making something HD means it's no longer the original is wrong. In most cases, making it HD is actually showing it closer to what it really looks like on film, making it more
like the original.
It wouldn't be straight ports of DVD content either, there's more to HD than just resolution. They would be able to take advantage of newer compression technologies and higher bitrates, giving us nearly perfect reproductions of the video masters of all those 80s and 90s shows.
Just as an aside, "Trials and Tribble-ations" looked really great on the Star Trek second season blu-ray set.