It's kind of a mix of both. The Jedi avoided certain feelings, fear, anger, hate, which they believed were paths to the dark side. Luke Skywalker rebuilt the same Jedi Order with the same confines as the old one, instead of building something new. Luke suppressed his emotions, which led him to blow up at Ben Solo, in a similar fashion that Anakin Skywalker blew up when he turned to the dark side. It's because of Princess Leia's acknowledgement and acceptance of her anger that she wouldn't fit in with Luke's Jedi Order with the rules he had in place, but if she were still alive, she may have fit better in Rey's new Order. Hopefully Rey can discover how to balance feeling ones emotions without falling to the dark side before she starts training the next generation of Jedi. Hope this helps!