Volatile reads are very fast, often nearly as fast as normal variable reads on most modern computer architectures, and in any case are likely cause problem only in a tight loop with high contention which is not the usage here.
Volatile write has a higher cost than volatile read and since we are okay with the write itself, read should not be a bother.
In general also we try to refrain from tweaking code that is working fine without any problems for years / decades.