EDIT: Perhaps BLM could have averted all of this hubbub regarding the phrase if they had just included the implied 'too'. As in, 'Black lives matter too.'
Both phrases are true and based on who is saying them can be fully believed statements.
The petty internal fights of Facebook co-workers crossing out do not matter. Without this article you'd never even know it is happening and just because someone is using the right shibboleth doesn't mean they are a good actor.
I also am definitely opposed to Zuckerberg for president, but I just don't understand the logic here. If they were merely writing "All other lives matter too," I'd understand where you were coming from, but I don't understand how crossing out the statement is praiseworthy.
I agree wholeheartedly. Had the messages in question said "Only black lives matter," I would support crossing them out.
But I don't understand how crossing out "Black lives matter" is supposed to be interpreted as "Yes, and other lives matter too" instead of the straightforward "No, black lives don't matter."