What is the effectiveness of the Safety Pin trend?

尺ㄖ
Purely opinion based discussion. 
So lately on social media I've seen people promoting the act of wearing a Safety Pin to show people from minority groups that they're their allies, and that they have a safe space with them. (This promotion seems to have started since Trump was elected so I think it's a US centric thing.)
Here's an example:
So I'm just wondering, if you're from a minority group, do you think it's effective for people to wear Safety Pins to show they're an Ally? Would you feel like you were safe around them? Or is this more beneficial to allies themselves instead?