I’ll have to find the source again, but apparently some Halo YouTuber(won’t give out any names)saw the numbers on the Halo tracker and did some math to get a rough estimate of how many people still play Halo 5. The amount of people on the Halo Tracker came out to about 150,000 concurrent players with over 60% of that being unranked. After the YouTuber did some math, the number of players who play the game daily came out at approximately 5,000.
Sorry if I sounded bad explaining this. If you want a better explanation, look up the video. It should be something around the lines of the title of this thread.