Let's assume you voted everyday and bought 2 AP resets for a month. You'd have 60 by the end of each month. If you went by the price of each AP reset being 9m and sold them, you'd have 540,000,000. Now lets do this for a whole year. 540,000,000 x 12 = 6,480,000,000 You would approximately have 6.5b from one year (assuming you could sell them all). Holy fuck.
If you just do a simple 365 x 8k NX per day, that would be 2,920,000 NX. If you just divide that by 3.1k (each reset) that would be ~942 AP resets. So multiply that by 9m each, you would get more like 8.5b rather than the number you explained.
Yeah that's assuming if you actually used up all your NX for a year. If we were to limit ourselves to twice a day, we would have a remainder of 1.8NX. After a year of doing all that, you would remain with 657,000 NX. I left that bit of NX out of the equation just in case you wanted to do something else with it (like gacha).