Redeye vs daytime matters too. On redeyes they may do fewer, or only come through with water bottles mid-flight.
In Y, I've had varying experiences on the # of drink services, ranging from 2-4. Given you can order a double, even +/-1 drink service can make a difference on how much I enjoy a flight
Personally, I feel 2 is too few, 4 impressive, and 3 acceptable. However, I wanted to get a pulse here before filing feedback on Alaska Listens.
While I enjoy doubles too, if you're writing to Alaska, maybe don't lead with "Alaska didn't serve me doubles 4 at least times on my recent flight."