The ratings trajectory of syndie Millionaire was consistent decline despite several
Changes in format and host.  More importantly, the station group stopped believing in it.  The data was fairly cut and dried.  The qualitative feedback was where the boredom was expressed. 

Most Celebrity (or Celebrity + immediate family/close friends) shows that played for charity up until the last 20-some years (IIRC) were either played on shows which aired on daytime or the early prime hours on local affiliates.  Dawson Feud, I believe, was the lone exception, but it centered more around specific TV show rivalries or TV families than actual specific celebrity families.

Those celebrity-charity episodes outside of primetime were either used for special weeks which added a little glitz and change of pace to regular civilian gameplay and/or ratings sweep weeks. 

Or, in the case of Celebrity Bullseye, (etal...)  it was alast ditch effort to save what ratings they had left

If you want nothing but celebrity players on a primetime game show, either play for a random member of the studio audience, or for viewers who enter for a chance to win from home.  Or do a charity / civilian winnings split.

I have no problem with Shaq as a host or presenter or comedic foil. Wasn't there a show by the name "Shaq Vs." at some point? Given how many athletes transition from the field of play to the TV side it is no longer surprising.

I'm curious what the evidence about how people won't watch regular folks play Millionaire. Were figures that easy to slice and dice?

One thing that I think ABC is missing is the utility of money. When David Duchovny was wrong on his $500,000 question he likely could have made up the difference if it was really important to him. It might have been several years but could be done. GSN just did the Top of the Charts block of shows and there were lots of folks who were past their prime and I'm sure the charities were important to them, but the charity wasn't front of mind for at least this viewer, it was each question as it came up on screen.

Go back and watch night two of Super Millionaire. Robert Essig comes off as a regular joe who is happy to be there. Watch as Regis says "and here's a check for $100,000." His demeanor changes. Each new level brings more elation as the money unlocks more opportunities. There are episodes of Debt where just winning a comparatively tiny few thousand dollars means wiping out a huge millstone around the neck of the winner, and the double payoff actually having that cushion to start over in a way.

Deal or No Deal certainly overplayed what the money meant, and the "what will you do if you win the $50,000" has become so trite that it is pro forma, but money is fungible and it has meaning for people.  For me, I knew I was unlikely to get on unless I really buckled down and practiced the phone game, and for all of the middle aged white guys on parade, lots of them were married and had kids, and even $32,000 of found money would be useful.

Lots of other shows are able to have regular people come in, play a game and win some stuff and then they are swept into the annals of TV history. Seeing someone win for the Salvation Army or March of Dimes just isn't the same.

To differentiate it from the tired syndicated version,

Picking this out because you have a reputation and history, when would you have put the daily version out to stud? I know several people who won money in the latter half of the run of engagement, and you have lots of people who were earning a salary from the show.

There's more going on than just the final product we see.

He’s made the show his own, although I think his delivery could be a little smoother at times during the Showcase, but I do love that his sign off calls attention to mental health awareness.

It feels like in the last 1-2 months of episodes, the staff as figured out how to time the show that they can leave a bunch more of the bits in. Not all of the bits land (I think it's Drew's nature to go too long with bits that don't work) but it's been about as close to Barker Era as one would be comfortable to get.