As a Roblox developer, It is impossible to give a humanoid a long (relatively speaking) distance to move without a workaround.
Currently, Humanoids will time-out and stop moving after just 8 seconds because of the reason outlined below (from Devhub):
“The reach goal state of a humanoid will timeout after 8 seconds if it doesn’t reach its goal. This is done so that NPCs won’t get stuck waiting for
Humanoid.MoveToFinishedto fire.”
This limit strikes me as being arbitrary and I feel like it could be removed or modified without breaking any games. I don’t understand in what situation MoveToFinished’s “reached” parameter would be useful, outside of code written as a workaround to avoid the 8 second limit. At the very least, this should be changed to only stop the character after it’s been stuck (ie, not changed position in a meaningful way) for a certain time.