Yes, all forums are opinions, mine included
Have 2 year old diesel (300 gal tank) I'm using weekly in my F3990 (regen mower), cat 416C 2000 back hoe (every now and then). and 955 loader and D3 dozer without any issues. The dozer and loader some times don't move for years, and never fail to fire up and go.
You imagine how many heavy equipment contracts would have an issue if diesel only last for 6 months. Diesel is oil, light weight oil, not gas, it does not evaporate or collect water from humidity.
You always have to worry about water getting in diesel for the pump to sitting, but have never heard of it going bad. Three years ago a buddy went a bought a Kubota small tractor that had been sitting for even the owner didn't know how many years. Turned out it had a clogged filer. Replaced it, and it fired right up with the original fuel
I have 2 boats and even ethanol gas last longer then a year and have never used stable or other additive unless its going to sit for more then a year
As always, this is just my opinion and recollection