Technically a subjective viewpoint is your view of reality while and objective one is factually based.   Objective perspectives should be consistent among a large group while subjective could widely vary.

Perhaps though, perception is reality, that is what you perceive and so believe is true.  Reality is what you believe it to be.  Contrary opinions to your perception are incorrect.

The world is mine

Philosophically if your reality of the world is based soley on your interpretation than it’s all about you.  If this applies to everyone humans would be unable to interract effectively.

Hence, we have  social rules.  As groups we define culture and imbed the associated rules into our behaviour through governance practices.  For example, this is done through implementation and enforcement of laws.

Addittionally and more importantly, our social groups define a cultural norm which is implemented through the process of having common beliefs and values passed from elders to their young.

So we can perceive our own reality but these perceptions are limited  by  cultural values for the common group good (the pack mentality) embedded in us from birth.  (Some don’t adhere to these values, but most do).

So our reality is all about us, within the constraints of the value systems we are nurtured with and the laws we need to adhere to or suffer consequences.

Does objectivity exist?

If reality is subjective, it  begs the question, does objectivity exist beyond an English word in the dictionary?  Can we ever say, our interpretation of anything is fully fact based?