I think Alex normal is in a really weird spot; it favors statics in some weird ways and is surprisingly non-casual-friendly for the way the content was designed.
It's all varying levels of pretty easy, but has fairly punishing mechanics. A4 is basically going to be a one-shot in DF or you're wiping for a lockout. Which wouldn't be so discouraging, except that the loot system is incredibly unfriendly to anyone queueing solo. You get a shot at more drops per week than under the WoD system, but you have a lot more competition than under the WoD system since basically everyone in your group is going to be eligible to roll on everything.
I think the difficulty tuning is probably roughly around where it should be, but the loot system is encouraging people to treat these as disposable grind content. Alex Normal isn't quite that easy, and so it winds up really frustrating to DF for inifnity. If it was something like you just had to do it once a week, instead of over and over and over, I'm guessing people would be more up for the areas of challenge it provides.
I think for these the loot should be for you only. 2 items drop, you pick one, or none if you want a specific one. There's still some RNG, and as such people run it more than once if they want a specific part, but if the part they want drop, they're done for the week with that floor. There's 4 floors to farm, and it gets worse as the week progresses and more and more people got their stuff since there's no reason to queue again once you're done, and as you said you always roll against everyone(at least in DF, but even in PF most people running a floor still need a drop and you can only hope the farm PF doesn't disband/have 2people leaving every run) so your chances of getting something aren't very high the more you run it. You could run A4 50times and not get a single drop even if you're not specifically targetting one, which is terrible.
I think another way to fix it would be to have tokens. Every run, you get one token. Once you have say 5 tokens, you can trade them for the drop of your choice of that particular floor(so there's 4 tokens types, one per floor) and doing so puts you on lockout(and obviously you can't trade if you're already on lockout). At the end of the week, the tokens are wiped, so they don't carry over. This way, you know that at most, you're running the thing 5times. It might even help with the queues since people would be more prone to run it 5times to get their specific drop, rather than run it once, get lucky and then not have to run it that week anymore. It'd also be great if you're trying to farm for glamour, as otherwise, fuck getting 4 chest tokens, the RNG within RNG is terrible and you need it 4 times over a month period? Meanwhile you'll probably be able to get the esoterics chest for doing EXDR like 4times a week for 2 weeks.