Fans believe that the HIStory Tour does not portray Michael Jackson (as a performer) in a favourable light, because of the extensive use of lip-syncing.
Aside from a belief between the fans,that also seems to be the truth because:
1. As you said,extensive use of lip-synching brings nothing but shame to the public image of the said perfomer. The more famous the artist is,the worse the case gets/could get. And rightfully so. I don't pay big money just to hear some old, CD album version vocals I could have easily listened to at home. No reason for anybody else to do so either. I can buy a poster and stare at Michael's picture and put the Bad CD in the background...and that way I get the "History Tour Experience ".Michael didn't even bother to,at least, pre-record his vocals before the show or in 96/97 actually...it's horrible.
2. While the show is mostly lip-synched,there are some,VERY FEW live moments in each show and for a lot of the shows those live vocals are simply horrible :Seoul 96(first night), Auckland 96(check the WBSS performance ), of course Munich 97, Tunis 96(again check the WBSS performance). Simply abysmal. (tho there are some great vocal moments even during this tour,ironically enough,for example the ad-libs in Beat it,during the second show in Seoul)
3. Not only his vocals (or more like the lack of them) are a big issue here,but during the History Tour also Michael's energy is ,during several shows,at the lowest point that it could be or that we had ever seen from him. Examples:Helsinki 97,Copenhagen 97,Seoul 96,Johannesburg 97 ,Copenhagen 97 Birthday Show. Of course there are energetic shows too there,but still. Still.
So of course the History Tour should never be released. It's by all means(energy wise,vocal quality wise,what's being lip-synched vs what's being sung live wise) Michael's worst ever tour. Just because he was smooth in his dancing here and there and just because this band happened to be maybe his best band,in the end it doesn’t really mean anything at all (after all Michael wasn’t playing in that band ,it was a selection of A class musicians,and we can thank Brad for the band sounding so good).
So yeah...