In crypto mining there is _only_ short term because if you haven't made your money back in the first few months you are in the long tail and will never break even.
For any algorithm that hasn't gone ASIC, residual hardware value is paramount. A previous generation GPU will still be worth something on the 2nd hand market to somebody looking to build a gaming rig.
What do you envisage an FPGA to be worth on the 2nd hand market when it is no longer clearly profitable for mining? How many FPGAs have been through ebay in the past year vs. how many GPUs?
IMO realistic residual value potential of an FPGA needs a long, hard look in the cold light of day.
This is ABSOLUTELY wrong.
People who started mining five years ago got their return on investment after 36 months so your argument is demonstratively false.
Right, but if it takes 36 months to earn enough to cover the cost of the rig, that means that net profit after 3 years is the resale value of the rig. Apart from the brief period of the mining craze that saw gamers pay stupid money for older GPUs that weren't good for mining, that's probably about 25%. 25% over 3 years is not exactly a goldmine.