This is the hunting forum, so many people likely aren't chasing 1/3 moa or trying to reach out to a mile. If you only put 10rds through your rifle a year it makes zero economic sense to reload.
But if you shoot alot, shoot wildcats, shoot big cartridges, compete, or want ammo that's better than standard 1.5 - 2.5 moa hunting fodder, reloading becomes mandatory.
As for economics, I just did the math on two of my bigger cartridges - 300 PRC and 338 Lapua. These are ELR/long range precision rifles, but there are plenty of big, expensive hunting rounds that can cost as much.
Costs below are actual all-in costs to me, including shipping and taxes.
300 PRC
New Lapua brass - $2.27/rd
N570 - $0.75/rd @ 82gr
215 Bergers - $1.12/rd
210M primers - $0.07/rd
For my very first firing on virgin brass, I'm at $4.21/rd.
Once I reach 10 firings per case (1000 rounds), which should be conservative, my average drops to $2.17/rd.
Compare that to factory 225 eldm match ammo. The cheapest I can find is $75/box of 20 ($3.75/rd) not including tax or shipping. By the time I get to 1000 rounds in 2-2.5 years I'll have saved at least $1500.
With 338 Lapua the savings on the first 1k rounds pays for all of my reloading gear and then some.
338 Lapua
New Lapua brass - $5.00/rd
N570 - $0.84/rd @92gr
300gr bergers - $1.76/rd
215Ms - $0.07/rd
For my first firing per box of 100 brass I'm at $7.67/rd. My average for 10 firings (1k rounds) will average out to $3.16/rd. Factory ammo is over $9/rd currently, so reloading 1000rds of 338LM saves many thousands of dollars.
It should be mentioned that I have all the components on hand for both to get past 1k each, so my costs are fixed. The savings will only increase as inflation jacks up factory ammo costs.
I also have other cartridges that have zero factory ammo available, and other like 308, creedmoors etc that I shoot in enough volume to justify reloading before I picked up the big boomers.
Comparing factory match ammo to my reloads, in my factory Tikkas (223 varmint and 6.5 creed CTR), I saw between 0.2-0.3 moa improvement with handloads compared to the the best match ammo I shot through either. Consistently, seen through many 5x5 and 3x10 groups. And ES/SD was literally 1/3 what I saw with the most consistent factory ammo I chrono'd.
With my factory Sako 7 rem mag, I'm nearly 0.4 moa tighter at 300m shooting with handloads (160 NABs, RL22 at 3k) than the best factory ammo I measured. Never calculated the cost savings for that cartridge, as it only sees 60-70 rounds a year, but it's probably not insignificant.
Reloading is certainly not necessary for alot of people, but it really depends on volume and accuracy expectations.