The article talks about using poor password attack vectors. just clickbait. And What do you mean again? The bots never stopped. The scanning never stopped. Here is a guide to protect your openssh https://www.cyberciti.biz/tips/linux-unix-bsd-openssh-server-best-practices.html
@nixCraft
i will make an admission. one my linux installation got hacked many years ago. basically it was my idiotic mistake. i forgot to shutdown ssh server or firewall it. good news was that it was simplistic ddos attack script.