For context we should look at the history of GBA since it dates back 20+ years and is not something 'new'. It has been 7+ years since the Privy Council added the + that includes: the consideration of other identity factors such as age, education, language, geography, culture and income. So it was about Women but now it is not only about Women.
Source: http://www.swc-cfc.gc.ca/gba-acs/history-histoire-en.html
Canada ratified the UN Convention on the Elimination of all forms of Discrimination Against Women (CEDAW) in 1981.CEDAW requires state parties to take measures to eliminate discrimination in political, economic and social life.
In 1995, Canada adopted the UN Beijing Platform for Action which requires all member states to "seek to ensure that before policy decisions are taken, an analysis of their impact on women and men, respectively, is carried out."
Also in 1995, in accordance with these international obligations, the Government of Canada committed to conducting Gender-based Analysis (now called Gender-based Analysis Plus) on all future legislation, policies and programs.
This commitment led to the implementation of Gender-based Analysis (GBA) in several departments, though different areas of government proceeded at different rates with differing results.
In 2009, the Auditor General of Canada conducted an audit of GBA in nine departments. The audit found uneven implementation of GBA and little evidence of its influence on decision-making.
As a result of the audit, Status of Women Canada along with the Privy Council Office and the Treasury Board Secretariat were required to table the Departmental Action Plan on GBA to Parliament. This plan increases the federal government's accountability for GBA.
Since then, Status of Women Canada has launched the modernization of GBA to GBA+. This updated approach emphasizes the consideration of other identity factors such as age, education, language, geography, culture and income.
Analysis that incorporates gender and these other diverse, intersecting factors is called GBA+.
GBA+ is used by the Government of Canada, but it is used by many other governments, organizations and companies also.