I don't know that ILD may be dormant or silent but it can be quiescent. I was diagnosed in Aug 2022. Over time I did four completely normal PFTs. Then, in Nov 2024 something triggered a flare. In a matter of days I went from being a healthy, very active 71-year old with NO medical conditions to being bed-ridden. I spent 55 days in hospital followed by 25 days in physical rehab. I have lost 55% of my lung function, as well as losing all the strength I ever had. I could not walk 120' without having to stop for a rest. I could not stand up to pee. I could not pick up seven pounds.
I am recovering now and I am in a very demanding pulmonary rehab program but I am a shadow of what I used to be.
And it's all because of that trigger, whatever it was. So the answer to the question is, even if ILD doesn't lay there dormant, all it takes is that one trigger to set it off. The results can be catastrophic. They were for me.