The best email client for Linux, Windows and macOS isn't Outlook

In businesses and homes, email is still a necessity for communication. But which email client is the best to use? You might be surprised to find out that it's not Outlook. I rely on email. In fact, it's my primary method of communication with the outside world. While most people are busy on Slack and other chat platforms, I still prefer email. Why? For one thing, I retain a digital trail of my communication. I can search through email threads to follow conversations with a single person (or multiple persons) with ease. Another reason is that I've been using email since the late '90s, so it's a very comfortable and familiar format.