Probably not.
There are people that still shoot WW2 era ammo and it always goes bang. Even more people shooting Vietnam era ammo and it always goes bang. I personally am loading match ammo with 1972 vintage primers and always goes bang. Why change carry ammo twice a year? Seriously!?!
This is one of those crazy conspiracy theories that makes the ammo companies erect. Ammo doesnt go bad in 6 months or 6 years or 60 years. Your grandchildren will have grandchildren that shoots your refuse.
A distinction is to be made between the Storage of Ammo , and the Carry of Ammo .
If Ammo is stored under vaguely not terrible condions , it's good for a long time.
【 Anecdotally , WWl era ammo brought home , and kept in sock drawers or humiditloaded in 1911 mags , didn't show inconsistencies for 75 plus years , and occasional failures to fire until close to 100 yrs . ]
But ammo carried on the person is subject to heat , cold , humidity generally , sweat , vibration , bumps jarring , and exposure to oils , lubricants , whatever exposures and contaminants that humans are .
From my chrono 'ing of handfuls of ammo that had know histories as carry ammo , inconsistencies show up after 3 - 4 years .
Hence the generally accepted LE standard of fresh ammo at least yearly. For me personally , with my own hardware , l consider that appropriate for stuff that is carried daily, every day . For guns & spare reloads only carried occasionally, it can stretch a little longer .
Without going totally down the SD Ammo rabbit hole , in 9mm , .40S&W, .38 spl , .357.mag , ammo within my preferences & preferred weights is commonly available in 50 rd boxes , and l buy at least 3 at a time .
That allows for a bit of function / accuracy confirmation for that Lot № , and several annual rotation of fresh carry ammo , without searching for availability, supply chain ,.discontinued by mfg , etc .
[ I have lifetime supplies of * actual carry ammo * for 124 HST , 165 in Both HST & Ranger w/ letters behind it , Plus 180 HST that l accidentally got a case .]