As to saying brothers when the WTS means brothers and sisters:
This has been an old, old problem that switches back and forth. For awhile the WTS was more diligent putting "brothers and sisters" and other double gender groupings.
My mother told me about an "anointed sister" who would sit in the front and every time the person on the stage said "brothers" when they meant brothers and sisters, she would say under her breath "and sisters." Everyone could hear her, that that was over 60 years ago.
Part of it that men from a certain era were trained by the vocabulary used by others around them. I could tell when a male member of the WTS would say men and women, he or she, brothers and sisters that he was from a generation that was used to hearing both genders mentioned where that was meant.
Checking the WOL with search, I still see frequent use of the phrase "brothers and sisters" now. But occasionally one slips through perhaps because an older male jw was in charge of the writing.