I have run into the same "multi-threading is hard" attitude among younger programmers. I believe that kind of attitude to be a career limiting mistake. In the interests of scalability, you may have to accommodate multi-process oriented concurrency anyway with such as techniques as message brokering, or CAS style counters available in various databases; however, it is always going to be cheaper to manage a pool of threads in a single process than to manage a pool of processes. In the data center, most bare metal servers have lots of cores where multi-threading really shines. I have noticed a trend in AWS to offer more single vCPU EC2 instance types for those unwilling to learn the joys of thread pool executors and linked blocking queues.