RE: 30lbs for Deerhunting
40 here in NH, 50 for Moose.
If you think about it, the minimum weight hasn't changed in years, meanwhile the speed that bows spit out arrows has gone up. So the speed todays 30lb bow can shoot are probably close to or greater than previous years 40lb bows, resulting in same or higher KE and Momentum.
Of course this ignores traditional bows, but a 30 lb compound is probably faster than a 40 lb recurve.