Many fewer than that, since people will buy more than one book. Number of kindles sold is between 20 million and 90 million (same source). Meanwhile the PS5 and Xbox Series X/S have each sold about 10 million: https://gamerant.com/ps5-xbox-series-xs-estimated-sales-clos...

But those are fairly new, so take the last generation. The PS4 sold about 100 million, and Xbox One about 50 million: https://www.theshortcut.com/p/how-many-xbox-one-consoles-mic...

So the leading game consoles outpace the leading ebook reader, but not by all that much. There are other gaming platforms, but there are also other reading platforms. Some people read kindle books on their phones, kindle books are 72% of the ebook market, and ebooks overall are a third of the book market.

1 in 16 seems like really high market penetration for a device that (practically) requires special-purpose hardware and whose offerings are primarily in English. Meta gives away not just it's platforms, but in many countries the data that those platforms need. In some cases it's the only zero-rated app. And they have gotten maybe 6 in 16 people to make accounts.