It is not a Chitubox issue, other than that CB assumes the unit of measure to be millimeters (as do most 3D CAD applications). The .stl file format (invented in 1987 by the Albert Consulting Group for 3D Systems) does not specify any unit of measure, it just quantifies how many units there are--it is up to systems sharing .stl files to agree upon a unit to use--this is a good thing as it makes the files universal.
.stl does keep "scale"--that is why the sphere remained a sphere--however it does not specify any specific unit of measure, which is why it was reconstructed as a smaller sphere.
This Wikipedia article explains this further.
Your experience is a configuration issue with your 3ds application is--make sure it is set to the metric system with 1 unit = 1 mm.
CB is actually "scalling" down as it believes each .stl "unit' is 25.4 X smaller (BC believes "unit' = 1 mm) than your 3ds application which believes 1 "unit" = 1 inch.
It might be "handy" if the unit of measure were configurable in Chitubox, but that's about it, applications used to create .stl content always are--just make sure they are set to 1 "unit' = 1 mm if CB is the intended destination.
FWIW; FreeCAD lets you change the units of measure for its own display and user interaction purposes, but it aways "thinks" and creates .stl files assuming a "unit" is 1 mm...