Who gets to decide what goes on the walls of our museums? That quiet but revolutionary question has nagged at Sonia Boyce ever since she first visited London galleries in her teens. Her 40-year inquiry into it, as an artist and academic, culminated in outraged tabloid headlines in 2018 when, as part of an exhibition of her work at Manchester Art Gallery, she temporarily removed a painting from the gallery’s “permanent” collection – JW Waterhouse’s Hylas and the Nymphs – and replaced it with an empty space in which visitors could leave Post-it notes recording their thoughts about the depiction of women in the gallery. For some male commentators, this…