Thanks; they illustrate very aptly what I pointed out earlier. The problem you're dealing with when working with film this far gone is very much at the toe of the curve, i.e. the shadows. They turn out flat - and on film as badly fogged as this, so do the highlights.
Part of the issue is also in the digital representations/scans, which have a black pointed that's lifted significantly above zero; let's have a look at e.g. the petunias with a black point zeroed out:
It now becomes more apparent how much of the center part of the image, i.e. the shadows, are compressed. If we were to salvage this, a steep correction curve in the shadow region would be required:
Things don't really get all that much better since a lot of differentiation int he center of the flowers is just lost (compare to the better exposed ones above).
You could do something similar for the other two images and find that they work the same. They all suffer from strongly compressed shadows.
If you look at the base of the film, the level of fog is probably something like 0.45logD (perhaps even a little more). Assuming it's developed to a gamma of around 0.65, this means there's 2-2.5 stops of fogging density going on. That's only part of the problem; another part is the sensitization (due to fogging) of unexposed/non-density-building silver grains which will form a cumulative exposure with the actual image exposure (cf. how flashing paper compresses highlights even if the flashing exposure itself doesn't generate visible density on white borders). It's this effect that destroys shadow tonality. So to fully compensate for the effect, you'd have to downrate the film by 2.5 stops or so plus an arbitrary amount to lift the toe of the curve beyond the effects of the unintended 'flashing' fog. You may need to downrate the film by 4 stops or more to get rid of the problems on the shadow-side of the curve. Your PlusX that was originally 125 is now around 8 ISO. Which of course isn't really the case, because this degree of overexposure will create problems with highlight compression, as you're pushing the image all the way up the curve and onto the shoulder. You end up realizing that the only thing the film does well anymore is the capture of very low-contrast scenes somewhere in the middle of the curve, so with generous overexposure, and requiring a strong contrast boost in post/printing, resulting in a very grainy image.
Yes, it does mean exactly that, at least if 'good' also implies 'technically good'. If 'good' means 'technically inferior images, but I'm still pleased with what I got', then yes, I agree. But this has more to do with the fun of shooting film, of doing things in a way you please and perhaps the anticipation involved in waiting for the images to come out. I understand I'm being a cpt. Buzzkill in pointing all this out, but I know from experience that the novelty of shooting film can wear off, and that many people start looking more closely at the results they get. They may then decide that the time and effort is still worth it, provided they have a fighting chance right from the start. My comments are aimed mostly at those people, or the ones who figure they may one day fall in that category.
Of course, anyone can and really should decide for themselves what they like to do. A friend of mine really enjoys shooting heavily expired (decades old) 120 film. Most of his photos are riddled with backing paper offset marks of various kinds, in addition to severe examples of the effects I explain above. I think the images are technically atrocious. He's happy with the experience. I have nothing against that (as long as I can go through the prints reasonably quickly and don't have to spend too much time with them).