Is that Assault on the Aerie of the Slave Lords? It's a good one... but an outlier. It begins with a fiat capture of the PC's, and, more importantly, it contains magic items for them to find/win as they go through it. It rapidly conforms to the expectations that I claim are present.
Actually Assault on the Aerie of the Slavelords is A3. The Pc's are equipped as normal in that module. The DM fiat capture takes place at the very end of that module.
A4-In the Dungeons of the Slavelords begins with the PC's stripped of gear and in timed event to escape before the volcano erupts.
Since I am home now, I can flip through my copy and see what wonderful magical gear the PC's have the opportunity to get before confronting the Slavelords themselves.
They start out with a few MU and ILL spell scrolls as a gift from a friend.
A giant ants lair can provide potions of extra healing and delusion.
If the PC's take time to obliterate a tribe of mycanids they may win potions of extra healing, growth, healing, invisibility, speed, and water breathing.
A squad of looters on the island can provide some mundane weapons and armor.
The PC's meet thier mysterious benefactor near the docks and he gives them a cleric scroll: cure serious wounds, cure light wounds x3, and a magic user scroll : sleep, invisibility, strength, dispel magic, hold person.
Thats it. The Slavelords boat has the PC's equipment and other goodies besides but they must be won.
There are no creatures requiring magic to hit, and the majority of the adventure must be completed without gear of any kind mundane or magical.
Ok, I'll ask again to the 1e/2e fans.
What then is your explanation for the table in the fighter's followers which clearly shows an increasing level of magic items for each more powerful level of follower?
How is that NOT an indication you were supposed to get more and more powerful magic items as you level?
Like everything else it was a guideline. That equipment listing was a suggested typical assortment. Depending on how tough the campaign was, allowing PC's to have magical gear on par with those values wasn't exactly game breaking.
Remember that gear was almost as easily destroyed as it was easy to acquire. Pc's were constantly losing items to failed saves and getting new stuff. If you were fortunate enough to have spare magical gear it was given to trusted henchmen rather than dumped at the local magical dime store.
Most monsters of the Pc's power level could be handled by a group of players without much magic gear. Gear made things a bit easier and were not required for the PC's to have a chance to hit a monster based solely on it's level.