Apple's "Activity Monitor" is a pitiful attempt by Apple to provide a process manager for macOS.
If you a familiar with the built-in Windows tools, "Activity Monitor" is more of a "Resource Monitor" equivalent, than a "Task Manager" equivalent. Though the Windows "Resource Monitor" is a far superior tool in that can show more detailed information, has more features and the interface has arguably a better usability experience than Apple's "Activity Monitor".
It is disappointing that "Activity Monitor" is the best Apple could come up with. Even if Apple was lacking inspiration for designing an activity/process/task monitor/manager, the Linux world has some amazing tools that could be ported to macOS with minimal effort. Apple could have a tool that is on par, or even something that surpasses what is built-in to Windows, but instead they have tool that is nearly useless.
* The layout at first glance looks useful, having tabs for CPU, Disk... but upon use you find out that each tab is just a different view of essentially the same columns.
* The viewable information is limited, missing details that I expect to find in even the most basic tools of this type, and I often find it to be useless when troubleshooting performance issues.