IMO I find that most of the fancy stirrups impede my riding and I prefer to use plain fillis irons.
Others feel otherwise - that's great for them. I find if I use any of the jointed stirrups I will be in pain afterwards so if someone would like me to ride their horse it will be in the equipment of my choice. I also prefer smooth leather reins, flatter dressage saddles and have recently mostly stopped using boots and leg wraps on my horse. So again - it is all up to preference. I'm not judging anyone for using fancy stirrups, I usually just cringe and feel my knees ache.
I have a lot of things that bug me but more and more I try to just ignore them and go about my business in peace. The thing that probably irks me the most are people that "must have" the flavor of the month saddle, bridle, etc.. and are just mindless consumers without thinking of their horse's health. Air filled panels on poorly fit "custom" saddles are the biggest culprit. My bridles are 15 years old, my saddle is a "classic" brand and my horses are happy and if they're not, then I change something. Buying a new saddle every year and subscribing to this thought that every month you must have the saddle fitter out is a bit crazy to me. I have experienced professionals who work on and with me on my horses and if they feel something is wrong we will change it. My horse won a CDI in a saddle purchased for him as a 5 year old. Imagine that with re stuffing the same horse can use the same saddle for a lifetime. That to me is not so far fetched as the saddle fitter "trained" by himself and who owns his own business adjusting a "custom" saddle by over 2" every month because of "changes to the horse's back". And each adjustment is $300. Yes "changes" to the "horses back" that have nothing to do with the company's bottom line...
Always remain a thinking horseman. If it aint broke don't fix it and if it sounds like the purpose is to line someone else's pocket book, it probably is. If it sounds dumb or far fetched, it probably is. Do what works for you and your horse and don't subscribe to any doctrine that requires consumption of kool aid or purchase of expensive tack. If everyone in the barn has the same brand of saddle, run. Not every horse in any barn is going to fit the same brand of saddle. Ever.
They say money doesn't buy happiness -- well happiness doesn't buy horses!