Before 3DS Max 2015, the OBJ Importer read objects via the 'g' tag. This dates back to the nineties through the Habware OBJ import plug-in and that plug-in is the basis for MAX's current OBJ importer.
As of Max 2017, the 'g' tag is ignored in place of the 'o' tag. Technically this is a logical change, 'o' tag for objects, but dismisses precedent. It ignores pipelines & workflows, user experience, & features of other software.
For example, in Modo one can select geometry and assign part names via the 'Set Part' tool. In Max 2016 and earlier these geometry 'parts' were all read as objects. Very useful as in many cases, it's far more efficient to have multiple objects defined within a single item/object layer in Modo and this is convenient to export.
In Lightwave Modeler, material names translate as object names in 3DS Max 2016 and earlier since material names use the 'g' tag. There is no 'o' tag substitute in Lightwave modeler, so exporting a single OBJ with multiple objects, to be read in Max is no longer possible without editing the OBJ file.
And that is the workaround. If the 'o' tag line(s) is stripped out of an OBJ, leaving only 'g' tags for named geometry, Max's OBJ importer will revert to its old functionality and read the 'g' tags as objects!
As someone who concepts & models in Modo, renders & animates in 3DS Max and leverages other software, constantly transferring geometry, what was once a very efficient bridge to other software and coincidentally incorporates recommendations I suggested for efficiency, has been an annoyance for several years.
The correct way to handle this, is to have the OBJ importer UI capable of reading either 'o' or 'g' tags as objects. If such a toggle option is problematic, since it would require a refresh of the OBJ importer window , the option could be added to Preferences.