After 10 years of a movement that culminated in protests in 2000 cities in all 50 states and 5 territories that had supermajority support in polls, the people who are still ignorant enough, feigned or otherwise, to say BLM means Black Lives Only Matter are numerically and politically insignificant.
No movement has ever changed anything by seeking to get 100% of everyone on board, least of all those most uninformed, hostile, and acting in bad faith.
Those who make hay out of the name and have ignored the movement itself for almost a decade now are a small, ineffective minority.
The largest civil rights protest movement in American history doesn't need to spend its time focus-grouping and hand-wringing about people like that.