This doesn’t seem to happen for me, at least not to the extent that time seems to be missing and I don’t know what I did.
It seems to happen more mildly. I notice how attention goes to thoughts when exploring thoughts is a focus, and it’s then by necessity less on what else is here in the sense fields. Certain thoughts and stories go in the foreground and the rest more in the background. But it’s all still happening within and as awareness, within and as awake space. So there is not any real “zoning out”. There is always awareness of what I have been doing and what happened. (Of course, having written that it’s likely to happen today or tomorrow!)
I assume this has to do with how much awakeness there is in the system, and our nature noticing itself through different states and situations. That’s always present, and that tends to shift how much attention is absorbed into thoughts. It seems that attention is not capable of being lost in thoughts to the same degree.
As mentioned above, there is more of a fluid shifting of what’s in the foreground and background. Thoughts may be more in the foreground while my nature is in the background but still in awareness, and then the reverse where my nature noticing itself is more in the foreground and thoughts and other content of experience is more in the background while still also in awareness.
I write this knowing that this human self cannot take any credit for it. In my case, the shift happened without any preparation or desire on the side of this human self. He was an atheist at the time, and more occupied by anxiety and trying to get through school than anything else. He has similarly not been a very good steward of it, at least not as he sees it himself. He has not trained thoroughly in one tradition and with one teacher over more than a few years at a time. He has not done much to prepare himself to pass it on or guide others and has not done it to any notable extent.
All of that is how consciousness seems to want to expressive itself, and all the content of experience it forms itself into, here.