Async fixes one problem with microservices. It does not fix the unexpected latency swings, the network timeouts and errors, the service disruptions when the microservice is unavailable, etc.
or the mismatch between request and response when using HTTP, or the overhead of using RPCs to protect against the previous scenario, or the issue of updating one microservice and not updating all the dependents
or the mismatch between request and response when using HTTP, or the overhead of using RPCs to protect against the previous scenario, or the issue of updating one microservice and not updating all the dependents