Depending on how old you are, you might remember the initial campaigns against HIV/AIDS were parading photos/videos of people suffering from the disease in later stages, ugly scenes, then came ARVs and those pictures were irrelevant, tried to advocate for ABC, A and B no longer work, because it was revealed that being faithful was based on trust and assumptions, creating a long web.
In a way the constitution allows for MWK by accommodating Polygamy,the r/ship will start as a MWK and end up being a Polygamous situation, that said, the only efficient way of preventing the spread of HIV/AIDs is the C-word hence the emphasis on using the condom.
This does not mean the media is encouraging infidelity, rather being realistic and not burying our heads in the sand and encouraging those who have chosen that road to use protection.
Kweli maombi yanahitajika