Networks are unreliable even if it is your local area network. In my career I saw some unrelated network equipment was sending a RST packet to load balancer with application servers IP address and resulting in service unavaiable errors. It took us weeks to find that out since it was happening very rarely and there were many layers between load balancer and application servers.
Network means slowness, connection errors, unknown results, etc all of which should be handled carefully.
On the other hand, I agree with your point of multiple teams. I tried to mean same thing with "used by other applications"
Also, with the current network speeds and memory availability, it's hard to imagine the war size to be a bottleneck in web development.
Depending on other services via a well defined network interface is good for decoupling teams. So it depends on the number of employees you have coding for the same platform, rather than on clients or anything like that.
> Also, with the current network speeds and memory availability, it's hard to imagine the war size to be a bottleneck in web development.
Network speed was not the problem, decompression / expansion of the application was. There were war files about 100-150 MB size. Also I saw one with size of 1.5GB however it was an exception. These may or may not be a concern depending on your CPU utilization, disk speed, memory, etc.
Most decisions depends on environment. For some environments, as you said, deployments are not a concern for microservices, for some they are.
Anyway, can you share which kind of environment even a 5 minute deployment would be a problem? Most places I worked at it took a lot more than 5 minutes to actually implement the change that's going to production, so deployment times were pretty much irrelevant overall.
Nit: those were always integration tests.