it isn't 100 USD for a pair. It is 100 USD for a single fitting. I said since they were buying thousands of them that they would probably get a 25% price cut $800 per tractor to $600 per tractor. Maybe they could get 5-15% more depending on quantity and what the profit margin is on the fittings.
I get your point that it is a pet peeve that they leak and are sometimes hard to get back on because of pressure built due to temp changes. The point you are missing is that this isn't an engineering problem. Engineers have already provided a solution (which you don't like because threads but that is something entirely separate). The reason is cost vs added value or perceived added value.
Over the life of the tractor let's say 10,000 hours (3 years running the tractor 10 hours a day every single day of the year) and let's assume that an L2501 leaks half of the hydraulic fluid out of it's case every hydraulic change, only from the 4 loader fittings, and you keep it topped up daily. None from pushed out gaskets, none from leaking threads just the loader fittings. that would cost you 75 gallons of hydraulic fluid extra or 1500 dollars total in lost fluid which barely covers the cost of the fittings that you paid. For most people losing half their case of hydraulic fluid in between changes is unthinkable because they pull their loader off once every 25 hours or less. So it adds no value to change the fitting to something more expensive and robust and charge an extra thousand bucks on a tractor.
However, if they can up the size of the hydraulic pump and get 1% more lift capacity ~100lbs., or do some tweaking to the HST or Gear Transmission so it runs 1% more efficiently gaining more PTO horsepower or better gph fuel consumption. What is worked on is engineered to work across as many different use cases as possible to have the best overall results as possible with as little wasted material as possible.
Unlike your roof that is specific to your house and maybe another 10,000 like it across the US so it's solution is a custom fit. You have to have a group of people measuring, roll out tar paper, chalk line everything, cut shingles to fit, get specialty shingles for any awkward bends that need made, and on top of that it produces a bunch of scrap waste. The tractor is cookie cutter. Every tractor within its model look within 1% of another and perform within 5% of another.
