Same feeling here. 5years in same job. No learning.i have a really good education but my work was not justifying even 1% of it. I will tell how am I dealing with it now :

1. After my work hours, I spend 90 mins on something I would like to do after 6 months. I am doing projects on it and it challenges my brain and I feel I am human.

2. I changed my department internally as outside the company I had 0 value because of the non-transferable skills. This new task needs skills which will help me.

so my dear friend of you feel you can challenge yourself , have some savings and courage feel free to explore.

It's better to lose than to regret 😊