True, However there are no current viruses in the wild for Linux.
Linux is not immune to virus and malware, and to suggest otherwise is completely inaccurate
Correct.
Yes, there are steps you can take to make the setup as secure as possible (protecting root, system updates, file permissions, user roles, etc.) but again, this does not make you immune.
Add on the complexity that you may not be affected by a certain virus does not mean it cannot live on your system wait for you to send a file/email out to a family member/friend to be infected.
Windows malware, Is a Windows problem,
I do not remember the last time I have seen a infected Linux machine.