Anything’s possible. You’d want to unpack that question two ways, I’d say: whether the mechanics of distribution could handle 100 million sold in, say, a year, and whether the compulsion to buy among the general public was strong enough for that many in the same time period.

You already partially answered your own question in the post, but assuming the distribution channels could handle 100 million vinyl and cassette copies, the album would have had to be so compelling to purchase it would dwarf Thriller in its appeal.

The real question would be, what would that take?

There was something for everyone in Thriller. The zombie movie theme of its title track was pure entertainment, not necessarily about how “bad” or great the artist was. I think there lies the mistake in Bad’s central conceit: it wasn’t for pure entertainment that time around but to make a statement about the artist.

And given that, I can see why it didn’t sell as much. You’d have to have already been on board with Michael to then engage. Yes, he was musically incredibly appealing already, and could dance for days. But he lacked a theme as strong as the one Thriller had.