Whether that is true or not is irrelevant in this discussion, I'd say.
If there are fans that liked the HIStory tour then great, that's fine. But in the wider scheme of things it will only prove a disservice to Michael's reputation and legacy were it released.
For anyone with any real credibility, you can't mime THAT much of a show and not take the hit for it. It's simple.
Some critics even picked up on the miming on the Bad Wembley release but those that did were happy to let it slide given that it was only used sparingly, and given the length and energy level of the overall concert. Michael's performance dance-wise was wonderful indeed. But you can't put on a live concert and mime 90% of it. You'll just be laughed out the room.
Why did This Is It sell so well despite all that miming someone asked? Perhaps a release of a HIStory concert prior to the This Is It announcement WOULD have harmed sales. After all, we're talking about a 12 year gap here. And for persons in the UK, no concert from that tour was ever shown on British television or released to market, so unless you attended a gig, actively searched for one online or read reviews at the time, my guess is you simply didn't know about it.
point is, This Is It sold out. Michael's credibility can't be damaged. The world is too big, and not everybody agrees on everything. There are a lot of aspects of Michael that others enjoyed that you didn't enjoy, apparently. You can't just go by you. You also can't worry about critics. Once an artist gets big, they get haters. You can't worry about that. A lot of people that nobody ever says anything bad about, don't necessarily do well in their occupation. A lot of people like the 2001 gigs. A lot of people didn't hear about a lot of things, and a lot of others did and don't care. Magic is magic. Anyway, I could certainly understand why MJ didn't want to tour anymore.
You really can't know what would 'damage' his legacy, in a hypothetical situation. I'm sure there are those who could feel justified at the idea that Michael was only good in the Thriller era, or that OFf The Wall was his only 'critically' good album, if people run scared and don't go beyond that. You can't go by what crap people would say. Nobody ever got anywhere being afraid of the opinions of negatories in their Mom's basements. You think Michael would have had such a long and storied career if he decided to quit as soon as somebody said something negative?
I've looked all over this site and there are a myriad of things that fans love about Michael that have nothing to do with the micromanaging criticism of this or that about him.
In fact, it was
when he was attacked that
more
fans were endeared to him.
There are musicians in many genres of music that want to explore the 'lesser known' MJ music, that got critically blasted in the recent past.
And, more importantly, in this subject matter, there are people who loved many aspects of MJ's later concert tours that you may not have given thought to.
I have heard that Motown 25 Billie Jean was entirely lip synched. Apparently, the world was ok with that.
If nobody ever said anything, I would never have given it any thought. And now, I don't give what people said about it, any thought. For me, I enjoyed it.