Have a pair of 50mm carbon clinchers on the way. I had a friend warn me if/when you need to replace a spoke you need to detention all the spokes. Otherwise it could break the rim. Is this really an issue?

Plastic myth

No

I build, rebuild and repair carbon fiber rim wheels all the time. The only thing that's really critical is that with some ultra light weight rims, the spoke bed is so thin that nipple washers are required. just ensure that, if nipple washers were present originally that you use them with any replacement.
Other than that, just replace the spoke, true and tension balance.

What’s the spoke count?
Low-count/high-tension wheels can be more tricky. I’ve had to adapt to that.
But because of the rim being CF - no.

Spoke count if I remember correctly was 20/24.

Then you are in the range where a technique modification is in order.
It might be sufficient to manually push the rim sideways to make tightening the replaced spoke easier.