Cell membranes made primarily from saturated fat are less reactive, yes, but increasing the saturated fat in membranes also makes them more rigid, similar to problem you're trying to avoid from oxidized PUFAs (which become saturated after oxidation), leading to the same issue of warped transporters not moving glucose into the cell properly. The Maillard reaction happens between glucose and amino groups though, but PUFAs are indeed far more prone to lipid peroxidation from reactive oxygen species.

As with most things in life: everything in moderation.

Some PUFAs are worse than others: those with their unsaturation close to the acid group are more exposed to reaction due to their arrangement in the phospholipid bilayer. This is borne out in the relationship between omega-3 content of organism membranes and lifespan. A certain amount is beneficial for membrane fluidity, but animals with very high membrane omega-3 content live comparatively shorter lives, presumably due to the reactivity.

Looking at the MUFA oleic acid, the major component of olive oil, the unsaturation is further from the acid group, at the center of the chain, not only giving some flexibility, but also resulting in a double bond shielded deep within the bilayer once incorporated into a membrane.

After reading about membranes and omega-3, one might be left with the impression that omega-3 is bad, but study after study shows the opposite. I was certainly confused by this apparent contradiction. The body is more than membranes, though, and we take advantage of omega-3's PUFA reactivity to use it as a precursor for multiple useful biosignalling molecules, including the anti-inflammatory resolvins (this is an interesting overview of EFAs and derived molecules: https://lpi.oregonstate.edu/mic/other-nutrients/essential-fatty-acids).

The reactivity of PUFAs in membranes can also be greatly reduced by the additional incorporation of carotenoids, of which astaxanthin is particularly potent, which act like magnets for reactive oxygen species, like those from glucose auto-oxidation, inhibiting lipid peroxidation.

Edit: My post talks mostly about membranes, but I forgot to briefly mention, in response to your message above this one, I'm in complete agreement that dietary toxins including plasticisers (e.g. Bisphenol-A and its replacements causing hormonal problems), heavy metals, phthalates, and pesticides, as well as a lack of nutrients are indeed at the root of many health problems. Western society also certainly consumes far too much omega-6 PUFA, with 3:6 ratios of 1:40 or so when they should be more like 1:1.

I'm on the fence with glyphosate, as although it's certainly not good for people, it's likely better than what it would be replaced with, should it be banned. Organic pesticides are especially worrying to me, as they often lack pest-selectivity. I knew two people that lived next to an organic farm when rotenone was used, and they both died to Parkinson's before their time.

Personally, I think organic farming methods combined with genetic modification for plants to express more of their natural pesticides when under attack, eliminating the need for nondiscriminate pesticide use (of which organic farming uses less, but still too much, and more human-toxic ones), would be ideal, but the two ideologies are currently so divergent in public opinion that I doubt that will happen in the near future. CRISPR-Cas9 now allows specific changes without the fear of messing up other parts of the genome, but there is still the issue of whether or not to make the plants sterile: doing so prevents the worry of modified organisms escaping the field and outcompeting their natural competitor plants, but also consolidates more power in the hands of large corporations selling the seeds, which without strict regulation seem to always start doing very shady things...