I agree and I think airguns are great. A pretty decent one can be had for a $100. You can find plenty of airguns and pellets available online still.Hrmmm.
I came here to mention that even air rifle pellets have dried up from many stores as well. A recent search turned up a single pack of lower quality Daisy .22s (of course I was after .177) and no CO2 carts at a wally world, and a severely diminished selection at Bass Pro. Found some a bit overpriced, wrong style, but better than nothing for winter plinking.
Not sure the air rifle exists that will "match" a .22 LR, but yes, it would be expensive. But for some small game, squirrels, rabbits, the .22 LR has way more energy than required -- many an off-the-shelf air rifle has the power and accuracy needed to get the job done.
I own a gamo co2 handgun for practice, a crossman/sheriton .20 and a .22. Had many others in the past including .177s. I much prefer the .22 over the .177s. I've squirrel and rabbit hunted with them. My nefew now hunts with a .22 PCP. $$$
A .22 long rifle has more energy than required but not enough to matter. We seldom use them because they louder. We usually use .22 shorts and longs (not long rifles) CBs (comical bullets) and have even used BBs (round bullets)
They do make big bore air rifles too. Some shooting .45 cal slugs weighing over 200 gr. They've been using them on big game for years. They too are more expensive and have less performance compared to powder guns.