Not really. World at war still has lots of people playing. Not to mention the fact that there are a lot of weapons back then and the killstreaks wouldn't be too powerful.

There may have been a lot of weapons, but they weren't all too different from each other.

They were different enough to have plenty of variety. You had several assault rifles good for medium ranges, both automatic and single shot. You had sniper rifles with scopes good for long range. You also had automatic sub machine guns good for close ranges and rushing the enemy. You also had the light machine guns perfect for setting up shop on a hill/ledge and laying down covering fire. There are many other different types of weapons. Besides, why does call of duty have to be about how many weapons you can use. Why can't it be like the old days where all that mattered was the atmosphere and the amount of fun you had fighting enemies.