IDK, we may be looking for different things. In my experience, the difference is very clear; 200-400 films tend to build a stop or more of fog per year, and the toe of the curve gets eaten at the same rate with grain going up and color shifting around on the color film. Sure, I've gotten acceptable prints and scans from 20-year old Superia 200 - although 15 year old HP5+, not so much; it's just very limited in its applicability. But if you scan, twist some curves and are OK with grain going up, then I suppose you could call it alright.
I fully admit I'm just getting more critical as time goes by. A few years ago I was OK with what I describe above, today I find myself buying a bulk roll of HP5+ because after having tried just about everything below its price point I found disappointing in one way or another (and you better believe I'm as price sensitive as the next guy!) I have increasing difficulty dealing with the realization when looking at a freshly processed negative "hmmm, I could have also shot this on fresh HP5+ (etc.)" Maybe it also has to do with the emphasis of my hobby shifting towards printing, and it's just frustrating to print from poor negatives. I've bumped my head onto that stone many times over; I guess I'm finally starting to learn. Well, to an extent...
The vast majority of my expired film (and I had lots of it!) I've given away a year or two ago. I never regretted it. The remaining stock I'm hesitant to use because of the disappointment that comes with the territory. At the same time, I'm also hesitant to let go of it. Fresh material doesn't put me into this catch-22!
Let nothing about this stop you from enjoying whatever you shoot, of course. I know and acknowledge the excitement of uncovering some old material only to find it still works (of sorts). There's an appeal to that in and of itself. And I also acknowledge that most of us are budget-constrained, some of us more so than others, and that it hurts in a way to discard something.