That Mac was mostly idle when you captured that screenshot. I'm not sure what you are expecting. Can you explain what you mean by "testing requirements"? Whose requirements? What are you testing?
If you want to show what a Mac is actively doing at any particular moment, change the Activity Monitor view to show Active Processes. You will find the overwhelming majority of the hundreds of processes you mention are not active, which means they are not using any CPU resources. By selecting My Processes as you have, other potentially burdensome processes are not shown, so they cannot be identified. However, that does not appear to be a factor in that screenshot because the CPU is mostly idle.
I suggest uninstalling "Malwarebytes". You don't need it unless you want to uninstall adware that you were deceived into installing, and even then you don't need it. Should you suspect adware is causing a Mac to perform poorly, Activity Monitor is a great way to confirm its presence. With a little guidance from your fellow Mac users, additional investigation can easily identify and eradicate what you installed, without resorting to installing anything else.
If you want your Mac to perform well I also suggest uninstalling Google Chrome. Google will burden any Mac of any age or configuration, even when you are not using Chrome. If Safari does not meet your needs, you can use Brave, Firefox, or Opera which you already have. They don't constantly burden your Mac to satisfy the Google beast's need to harvest the information it wants.
