Weapon proficiencies would have been fine, imo, if weapons were balanced against each other, but in each category, there was always a "best" option. Now granted, the differences tended to be small, like, if you use a knife over a dagger, you're missing out on half a point of damage on average, but the upside that knives can do slashing damage or piercing wasn't really noteworthy most of the time. Broadswords were only slightly better than the Khopesh (which really was more in the game to support specialized campaigns I imagine), and slightly better a longsword against regular foes, but the longsword had this huge damage increase against larger foes that more than made up for it.
Weapons introduced in later books tended to make PHB ones look sad, like the katana or the longspear. And then on top of this, there was the fact that the DMG treasure tables perpetuated Gary's weapon bias, and didn't take into account newer weapons anyways, rendering a lot of choices moot unless the DM didn't use them...but then, without any real guidance for when/if/how a player should expect to find items, they were playing it by ear (and a few DM's found themselves terrified of player power and became very conservative about it compared to published adventures).
And players did quibble over small variances in weapons "oh this one does 1 more point of damage on a good roll!" because there weren't a lot of bonuses to damage you could rely on! You either had the opportunity to have a high Strength, you found a way to get weapon specialization, or you hoped for magic (or maybe a quality weapon for that non-magical +1!).
And the shocking thing is, to this day, weapon choice makes up a very small amount of a melee character's damage (and weapons have become even blander, with less variance between them). A warrior's choice of weapon should really be a big deal, and often times, it really isn't.