Is the 'man figure next to the clock' a good feature to enable?

I assume you mean the Personal Focus indicator. You can read more about using any of the Focus modes here and set them up to reduce distractions, silence call from some people, or only allow calls from some people, and do the same for App Notifications. You can schedule a time to have it automatically turn on/off or manually turn it on or off. It is all in here:

• Set up a Focus on iPhone - Apple Support
• Turn on or schedule a Focus on iPhone - Apple Support