no it really doesnt on these forums you have a really biased answers, because they are the more or less hard core elderscrolls fans, Oblivion did sell better (last time I checked it has been a while) though so people did like it more than morrowind
Selling more copies in no way relates to which one people liked more, and of those who played both, most seem to have certainly not enjoyed Oblivion more. The entire games industry grew a lot between the release of Morrowind and Oblivion, and a person doesn't know whether they like a game until they've bought and played it, so a copy sold doesn't = a copy preferred over the original. Likewise, of those who only played Oblivion, how would they know which they prefer when they didn't play Morrowind? Later Need For Speed games sold tons more than the earlier ones, but people who played both far prefer the earlier ones. Duke Nukem Forever is going to sell more than Duke3d, but everyone agrees that DNF is total garbage whereas people agree that Duke3d was awesome.
Oblivion sold more because it was released after the games industry had grown much in size, and because it was much more commercialized and promoted on the new consoles at the time. None of that suggests that people liked it more.