In some areas of the world where network and/or device performance are limited such a low latency will be impossible to achieve indeed. Inter regional broadcasting also comes with a latency penalty, but with good CDNs like provided by our partner Akamai you can already get a 1 second latency in many cases. That being said the buffers will be very small and we don't recommend using that yet in general.
HLS and DASH are similar indeed, but I think the main reason that HLS is still used a lot is that it's the lowest common denominator; you can get it to work everywhere. Perhaps in the future that will be LL-HLS, or something else entirely, but for now most really low latency broadcasting that I'm aware of is using DASH with HLS as a fallback (i.e: CMAF). But I could also be wrong about that of course :-)
HLS and DASH are similar indeed, but I think the main reason that HLS is still used a lot is that it's the lowest common denominator; you can get it to work everywhere. Perhaps in the future that will be LL-HLS, or something else entirely, but for now most really low latency broadcasting that I'm aware of is using DASH with HLS as a fallback (i.e: CMAF). But I could also be wrong about that of course :-)