This question was asked to one of seniors in a programming interview. According to me, because the sizes of memory accessed by softwares are increasing, the memory may soon be exhausted. So in this case if we used swapping, it would be inefficient. So we would go for virtual memory because it maps the memory in the disk to the main memory.
But if we can have very huge memory then would virtual memory be of use? And please tell if the above answer needs some modifications.
I suspect that the questioner was confusing the benefits of logical memory with virtual memory. Under logical memory, each process has its own address space providing protection. In addition, the shared kernel address space is protected from improper accesses by user processes.
In other words, while virtual memory is likely to go away in the future, logical memory translation (often conflated with virtual memory) is likely to stay.
Virtual memory is still important. One of the main reasons is that it provides protection. While this could be accomplished with a memory protection unit which provides something similar to x86 segments as opposed to a memory management unit which provides virtual memory, this has problems with the next important things virtual memory provides which are sharing and having things memory mapped. Trying to do something such as a shared memory segment (as in the System V IPC shared memory) is very difficult with just a memory protection unit and similar for memory mapped files. Also if you have only a memory protection unit dynamically increasing the memory space of a process is difficult has you are limited to physically contiguous memory.
In short another way to look at this is virtual memory provides one of the fundamental abstractions that an operating system provides to a process in Unix like systems and in most two tiered privilege level systems. While initial part of this abstraction was to make it appear as if the process had access to more memory than the system might have there are other abstractions that virtual memory provides that aren't overcome by simply having lots of RAM.
As for logical vs virtual while the words can have different meanings for different architectures I recommend this SO question.
