It doesn't have to be TNG S8 to qualify as a sequel. I fail to see what is achieved with these nitpick-y distinctions. Are they trying to soften the blow for fans who think it's a direct continuation of TNG, or attract new viewers who might be reluctant because it could be a direct continuation of TNG? Or they're just attempting to be unnecessarily clever about it all. If Patrick Stewart is in a Star Trek TV series playing Jean-Luc Picard, with appearances from several TNG characters, then it is a sequel of a sort to TNG - regardless of word play.