Hollow-Core Fibers (HCF) open the way to reduce Internet delay since light propagates at 300,000 km/s (instead of 200,000 km/s as in conventional silica fibers). However, understanding the impact of this reduction on the total Round-Trip Time (RTT) of a connection is not straightforward, since there are multiple sources of latency, not only propagation delay. In this article, we analyze potential latency reductions on real RTT measurements for different continents across the globe. We find that in those countries where RTT is near its theoretical minimum, HCFs can have a dramatic impact on RTT reductions since the majority of latency is due to propagation delay.