I don't know where you have been looking for the last decade, but your statement is incorrect. Yes, there have been periods of scarcity and high prices over the last ten years, but there have been equal times of plenty and low prices also. Prior to each of the last three elections the industry was practically giving ammo away with sales, mail-in rebates and other incentives.
In 2018/19, all calibers were there for the picking with excellent prices. In 2018/19, all calibers were there for the picking with excellent prices.
Examples:
Remington 9mm @ $9.00 a box/50 with a $5 mail-n rebate. Crazy cheap! 40SW $11/box. 45ACP $15/box, etc
Federal hunting ammo, buy 4 boxes get $20 mail-in rebate.
223/5.56 Winchester and Federal for $9.00 a box/20 + mail-in rebates.
22LR $0.03 ea for bulk Federal, Win, CCI and Remington
We are now in another period of shortages and high prices. Availability is getting better. Prices are starting to come down. Barring some other event (pandemic, political, geo-political, etc) ammo should slowly continue to come back in stock. Prices will be a little higher than before due to inflation, but should be reasonable. When prices and availability come back around, I suggest people to buy it cheap and stack it deep. Gone are the days of stopping by Walmart on the way to the range to grab a box or two for that afternoon's fun.