I would tend to not blame the lubricant (FluidFilm), however, upon reading the MDS and the applications on their website, it appears that it can cause swelling of rubber, and not specifically mentioned, I would imagine, certain plastics. It also leaves a film that, over time, IMHO, would attract dust and grit that would be blown into the air while driving down the road and then deposited on/in the hinges.
I have tried graphites, but, have found problems with their color (looks like @$#$ running down the side of a white trailer) and longevity. I use a spray PTFE...a teflon lubricant that dries to a white film that won't remain tacky or "fluid" and it is white, so, it is less of an eyesore, lasts a long time and most importantly, does not contain silicone.
DuPont PTFE Spray
If you've read any of my posts that have anything to do with caulks and lubricants, you'll know that I'm not a fan of silicone. I used to be in the medical field (retired) and we did a test (I was a CT / MRI researcher) with silicone and found that it migrated many feet from where we initially sprayed; contaminating all the surfaces and making any other surface treatment less than adequate. If you, for instance used a silicone spray on the hinges, you could test the sidewall surface sometime later and find silicone on it. If you then waxed, or tried to, over the top of it, the wax won't adhere as well as it should, etc. and that applies to caulk compounds also; that's why most manufacturers don't use it and the best aftermarket boat and RV sealants don't either. Silicone is also difficult to remove once it gets someplace that you don't really want it; that the nature of silicone. It has its uses, but, not, IMHO, as a general purpose lubricant or a "slickening agent" in caulks and sealants that may need to be gone over again at a later time. Enough of my preaching!
My guess would be that the hinges may contain rubber O rings and / or plastic bushings that have swollen from the use of the FluidFilm and these swollen points would compound the issue over time by collecting enough grit to actually cause the hinges to sieze up on you. After you replace the hinges, try to stay with a dry film lubricant. In RV usage these dry films will usually do a good job and don't attract nor hold dirt. PTFE has the additional benefit of staying where you put. Another good "dry lubricant" that I use where it doesn't show much or I want a really good slick surface is a product called SLIP Plate graphite spray paint. Sounds bizarre, but, I use it on my folding steps, stab jacks, the pin on my fifth wheel hitch, etc. It dries solid, it will wear off, but, when it does wear off, it leaves a graphite film embedded in the metal. I spray it on the fifth wheel plate's pin (the part captured by the hitch itself) and at the end of the day, the paint is gone, but, the pin itself is slick as a ______ (fill in the blanks)
SLIP Plate spray graphite paint