It is the same as is Driving licence important in the real world or society? Everyone can do the job but the licence act as a Quality Assurance that s/he is a Qualified Person because s/he meet the standard requirement.
Having licence have more accountability for his/her action. A pedestrian (without driving licence & deems don't understand the law) illegal dash across the road even if there is an incoming car has less liability compare to a Driver (with licence & deems understand the law) travel in a very slow speed but still hit the pedestrian.
As for whether is there a needs for Engineering graduate to be PE depend your career objective. For example, you got a MBBS. Do you use it to register with SMC to become a Medical Doctor or just treat it as an academic certificate to find relevant jobs like Patient Care Assistant & Research Assistant or non-relevant jobs like Administrator & etc?
That one is a national award. For example, SAF Good Service Medal (5 years services award).
Totally not related to licence like PE or qualification like PhD.
Don't understand what you are trying to express.