The Archive bit is hardly ever even used anymore. Basically the Archive bit gets set (enabled) whenever a file is modified. And some legacy backup programs would clear that bit whenever they backed up the file, in order to indicate that it doesn’t need to be backed up anymore — until the file gets modified again, at which point the bit gets set again to indicate that it now needs to be archived again. But I don’t know if any backup applications in use here at the end of 2021 still rely on the state of the Archive bit to determine what needs to be backed up. In any case, it’s not something you should be modifying directly.