Yes. ScummVM only used the game data, and runs it independently from the original executable files, so it can easily implement its own mouse controls. Hence it is not an emulator, but an interpreter, and, while great for nostalgia, never 100% like the real thing.
Whereas Dosbox, and every other emulator, offers the full experience, including all flaws and drawbacks that were present in the original OS and games.
Moonlight streaming does another thing, and I’m not even sure if it would work out for all DOS games. Because you would still have to deal with the weird input controls those devs of old were doing. So chances are that work put into a similar implementation would be ultimately a waste of time. ¯\_(ツ)_/¯