How to reconcile desire to succeed in academia/willingness to prioritize research with ethical concerns about fair work practices?
I will avoid the discussion about &quot;fair work practices&quot;, which I find problematic for the reasons explored in the comments. Instead, I will address two questions that I think are at the heart of your question.

Does the fact that you work long hours contribute to a &quot;culture of overwork&quot;?

Arguably, no. Investing a certain amount of time into your work is not an endorsement for others to follow your path. There are large individual difference in how much capacity a person is able and willing to commit to their research. You are responsible for keeping your own mental and physical health in check, but not for the health of others.

How can you avoid contributing to a &quot;culture of overwork&quot;?

This is mostly about how you interact with others. Fundamentally, adopt a mindset that acknowledges and embraces individual differences.

Don't glorify worked hours as a performance metric. Don't walk around telling people how busy you are.

If you're in a position where you supervise students, encourage them to work the number of hours that feels right for them. Encourage them to view their time as a valuable asset and use it in a productive way. Don't scold them for not putting in a certain number of hours (assuming that they don't clearly put in less hours than they are contractually obliged to - if so, first try to understand what's going on).