I don’t hunt with my AR’s, they are strictly for fun.
If I want big game (i.e. deer) I hunt with Rem 700-BDL in .30-06. or the Mauser M98 Mag in .338 Lapua.
When out for just fun, who the hell wants to reload magazines all the time. You can easily squeeze off 5 rounds and then have to reload another mag over and over. 4 mags for one 20 round box, or 2 mags for three boxes.
I am not suggesting you should hunt with an AR. However, if you did, for some reason, want to hunt with it, a 5 round magazine might be required.