Stephen noted the interest and he actually didn't look too bothered that she seemed eager to know. He really only got a chance to talk to Christine and to Wanda about different realms and the ability to travel to them, although it was trickier for the inexperienced. There were still things on the astral plane that could harm one's soul or thoughts, after all.
"You don't need to apologize. It was a glimpse. I remember that it was crystaline when I entered, and everything considered infinitesimal looked...enormous in comparison to myself. It was incomprehensible. And it seemed to go on, forever." He didn't scowl, as the memory of it was more fascinating than he could describe. It was one of many places that the Ancient One showed him for a reason, although he still didn't know why. Nor did he know what Hope's personal stake was. "If it's personal, I won't pry..."
After a brief moment of contemplation, he said, "...but my job...is a master of the mystic arts. I protect this world and everyone on it. And, by extension, everyone in this universe. Earth is my priority. Obviously. I mean, we are stuck here."