The wax boxes all say "all 660 cards in one series"
The box topper ad says "all 660 cards in one series"

Just because they made a special post season set for a large retail customer does not mean the traded were part of the main set.

if it's called a "traded set", why would it part of the "regular set"?

parsing words to say a "complete set" should include both is pretty ridiculous in my view.

sorry to see this happening.

Who is in charge of this hobby anyway ? Let's ask them the official position.

I thought you were at least on the board Al???

When were the Traded cards called a set by Topps? The fact that Topps issued it as part of a complete set tells me all I need to know.

Why is it ridiculous when Topps issued a complete set and it included the Traded cards?

I disagree on both points 1972 Traded cards are clearly part of the set. One of the ways to tell that is they are on the checklist.
1974 Traded cards have there own checklist because they are an insert set.

The box topper ad in later boxes says now includes traded cards. Why did Topps put multiples of traded cards in most packs if they didn't intend them to be part of the set? Most collectors would already have most if not all the regular cards. Topps clearly didn't intend for them to be inserts or chase cards. They wanted collectors to get lots of them.

As you stated later in the season they inserted Traded cards. A typical Topps marketing strategy to add an insert set. Most boxes did not contain traded cards.
By the way this is a 1982 Topps Factory set and it did not include the traded cards. Now you could argue that there were no traded cards in packs but in 1985 traded cards were issued in wax and as a box set but the Factory sets only included the base set again no traded.

The packs that contained 1985 Topps Traded cards only contained traded cards, no regular cards. In 1974 & 1976 the regular and traded came in the same packs.

74 Traded are Inserts

It comes down to a collector's mindset. At the time, everyone (contrarians aside) saw the Traded set as an entity unto itself. The people buying packs looked at them as a separate set with a separate checklist, like a weird added bonus. Although the word 'bonus' doesn't work too well, because the terribly airbrushed headshots look God-awful. That speaks to me the loudest.