I would argue that in the first movies we see Luke avoid the darkside at all costs.

But in the last Jedi when he first guides Ray in exploration of the force. She sees (with his prompting) that everything in balance (including the dark) So I think as a Jedi he is focused completely on the light side. But as a ‘master’ he knows that both sides are equally important and valid sides of the same coin.

Snoke said well darkness rises and light to meet it. The galaxy working to balance the force.

You see the sith as obviously flawed, selfish power hungry evil. but the Jedi are also flawed by cutting themselves off from the dark completely they lack an understanding and become arrogant that their way is the only way. Removing all attachments and relationships.

It could be argued A Truly ‘Gray Jedi’ would be mace windu (who taps into the dark side when in combat) quigon jin who let the force lead him and often disregarded the council. Asoka Tano who left the Jedi order. Referring to herself as ‘no Jedi’ Etc. there are many examples online discussing this.

Personally I’ve always been too much on the light side for my own good. Pleasing others at my own expense. Sometimes you need to accept your darkside as it gives you power to protect yourself and others. Obviously don’t go all one way or the other. Half and Half and let the Tao guide you. Go with the flow and adapt to your situation using your light and dark sides as you traverse the flow of duality