Well, let's explore that, using a little common sense and an analogy.
Let's say you are testing a car. The engine has been tested on a stand, out of the car. The transmission was tested when it was assembled to make sure it rotates. The tires were inspected when they were manufactured.
When the car is built, does this mean that you don't have to test to see if the car will actually work?
How were the interfaces between all those components tested?
Depends on the project. If its straight forward single server, single application ..... unit testing may be more relevant.
What about a platform with about 200+ odd servers with about 70 odd applications running 3 different buses with a backend SAN .... all interacting representing 5 different Business functions ? Would you say unit testing is "More adequate " in this case ?
Sufficient to satisfy a requirement or meet a need.
Not sure something can be more adequate, looks pretty binary in definition (something is either adequate or not)..... yeah yeah call be a grammer Nazi.