This was noticed during the Technical Alpha, it was later fixed in this Blizzard post regarding the Technical Alpha Learnings.
Loading Screen: Character Vulnerability & Time
Characters will no longer spawn in a hostile place until the game is fully loaded, preventing characters from getting attacked or harmed during a loading screen. Additionally, the overall load times will be faster.
However, for whatever reason this fix didn’t make it to the live release of D2R and it hasn’t been fixed since then. It would be fantastic if it were fixed, a lot of character deaths result from loading into the waypoint and being attacked while being unable to respond. This is especially problematic for hardcore players.
The Bloody Foothills waypoint is a particularly dangerous example, as you or your mercenary can attract the attention of Eldritch and his pack which can be fatal if you have long loading times. It’s almost like the old days of D2 LoD where Duriel could kill you while you loaded into his chamber, or where Flamespike the Crawler could kill you when you take the Inner Cloister waypoint.
Fixing this would also resolve an issue within the speedrunning community because currently you can move during the loading screens, which is a factor that speedrunners need to take into account.