That's a fighter with ~12 strength vs a fighter with 18/## strength .. yeah that's a huge gulf regardless of edition. I guess the positive is if gauntlets of ogre power come up the 18/## fighter will probably let you take themHaving played an AD&D fighter without strength bonuses next to one who had 18 percentile strength the imbalance was continuously noticeable to me as a player and was detrimental to my fun as a player.
I have played B/X basic, AD&D, Rifts, GURPS, White Wolf, and 3e where you can have lots of imbalance between characters.
I prefer balanced PCs as a player and as a DM.

Though balance can mean different things to different people though, especially between a player and a GM.
That's one of the reasons I'll always want to use point buy. I'm okay if I play a PC that isn't always as powerful as PCs with other classes (although I find 5E did a pretty good job here most of the time), it's that I've seen people roll at the table and in 5E we would have had 1 PC with a 20 in their primary stat (with no bad stats) and one with a 14.
Of course it's all personal preference, but if given a choice between point buy and rolling I've taken point buy every time.
Yeah I wish there wasn't a stupid voice in the back of my head that always says "hey rolling is fun, let them roll!" when it's time to lay out the rules for character creation for a campaign. sometimes I can ignore the voice, but more often it's slipped in somehow in some from.