My copy of UK2 is 1983 in the copyright, but its a UK copy... Did they release earlier in the uK? .... I don't have a copy of b7, but it was originally published in 1979, republished in 1984. C3 was 1984 according to my copy, and I don't have O2, wiki says 1984, though that again is a UK release date
Speaking as an adventure junkie who was well into the hobby by then- never played any of these and I've only seen a couple of them.
Pretty much every adventure that I looked at from the late 1e period until a few excellent late 2e additions was total crap.
Believe me, quantity does not make up for quality. This was the era of railroad adventures, where the modules punished you for not trying to be the good guys.
The good adventures were in Dungeon magazine in that time period IMHO. The original list really shows the fragmentation of TSRs game worlds.
This was also the early days of 2e, with (it seemed) TSR trying to capture the market of game accessories and modules. 2e was also the "clean up our image" edition - get rid of demons and get rid of evil characters - so there is definitely a basis for modules assuming the PC's would be the good guys - that was the push for 2e, especially early 2e.
This predates the advent of splatbooks, rules additions, etc. books, so modules were pretty much the only accessory published with any regularity. The efforts to support multiple game worlds was pretty clear. If each one had found an audience and role playing games become a mainstream pastime, that might be an effective business strategy - make D&D "all things to all people" and capture more market share. But that's a bit "if"!
When I first read the title I thought it said "a bummer year for adventures".
Then I looked at the list...and thought it again.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.