I have noticed something interesting, when i create a new host entry with Mamp pro (from the software interface) , Mamp Pro manage to edit etc/host file!
127.0.0.1 test.dev # MAMP PRO - Do NOT remove this entry!
::1 test.dev # MAMP PRO - Do NOT remove this entry!
i can see all my local flywheel host entries in the same host file by the way.
So, etc/hosts is writable for Mamp Pro but not for Local Flywheel 
I also have change the chmod permission like this but it didn’t t change anything:
sudo chmod 664 /private/etc/hosts
i also open etc/hosts in finder and change permissions for the user’s ‘wheel’ to read and write but i have noticed that after restart local fly wheel, the user ‘wheel’ is back to ‘read only’ permission…