sure, Bookscan is about 25% of US sales, TSR numbers are 100% of worldwide sales. Stop equating the two. Done...
NOT Done.
To the TSR sales add in Fiend Folio, Legends and Lore, Deities and Demigods, Unearthed Arcana, Battlesystem, Dungeoneers Survival Guide, Wilderness Survival Guide, Tales of the Outer Planes, Lankmar, Moonshaes, Kara-tur, Manual of the Planes, Greyhawk, 70+ modules, and around 10 million copies of Dragon magazine
IF the bookscan is 30% of all 5E sales then it
MIGHT have sold about the same amount as 1E
IF you don't include Dragon magazine.
So going by your numbers
I get a conservative
PHB 6.5M 5e vs 1.6M 1e
DMG 3.2M 5e vs 1.3M 1e
MM 3.2M 5e vs 1.1M 1e
Sets: 6.5M 5e vs 3M 1e/Basic
But you are accounting for 80% of WOTC 5E total sales with those 5 products (not including sales of the cookbook or DM screens) and only about half of the TSR sales we actually have numbers for and we don't have sales numbers for 80% of the TSR products.
For example - TSR sold 600k copies of Monster Manual 2 and by most anecdotal accounts and commentary sold less of that then they did Fiend Folio.
Deities and Demigods was popular enough it went through 5 separate print editions, caused a nationwide revolt, was burned at book burnings and was actually pulled from shelves ... and we have no numbers for either it or its replacement Legends and Lore (which also had multiple print editions).
They sold around 2 Million Expert/Companion/Master/Immortal sets that we know about and are core rules not included in the basic numbers above.
Like I said if you accept at face value that 5E reported bookscan sales are about 30% of the total you probably are about equal with 1E if you don't count Dragon magazine and still way behind if you do count it.
Done!