It's typically difficult to just pick up a $400 off the shelf rifle and shoot sub MOA in my experience. Sure it can be done, but accuracy is the sum total of all input. Ammo quality, barrel, trigger, shooter input, weather.
I have three centerfire rifles that shoot sub 1" consistently. One is a Windham Bushmaster Varminter. Air gauged Wilson barrel and 6.5-20 Leupold VX-III scope. First round hits on prairie dogs at 300 yards are common. I spent quite a bit of time working up hand loads. I use Nosler BT's over 26 grains of Varget. Excellent trigger, probably +/- 2#.
Second is an AR in .358 WSSM. Shilen Ultramatch barrel. Leupold VX-R 4-14. Nosler 180 grain bullets. Lower has a 1 1/2# Timney trigger. Shoots .4's pretty consistently. Killed a deer at a lasered 279 yards. This rifle, scope, and loading dies cost over $2k.
Third is a .204 CZ. Took a while to get loads worked out for it. First groups were literally 3-4". Got the barrel settled in and found 39 grain Sierra Blitzkings. Bughole groups now.
I suspect most of the guys that think it's impossible to have a sub MOA rifle are the same ones that think a cheap rifle/scope is just as good as a better one. Spending a lot of money doesn't guarantee an accurate rifle, but it increases the odds. Hand loads can make a huge difference. It's usually a matter of controlling variables.
Number of years ago I read an article about bullet quality. There is a machine (Juenke?) that can be used to check bullet consistency. When the jacket of a bullet is swedged over the core, it sometimes leaves a very tiny void. This throws off the rotational balance (think balancing a tire). Only the bullet is doing 240,000 rpm out of my .204. Doesn't take much of a defect to make it wobble