Just a quick note first: Last week's meeting - requires an apostrophe.
Given that the first person didn't indicate the response was unexpected, that's the only truly likely scenario.
Dozens of possibilities exist about what the first speaker is referring to. The last subject discussed at the meeting. Whether he should ask out the cute girl who was also at the meeting. The performance of the person who led the meeting. It could be so many things.
Then the person replies. Unless the first person says, "No, no! I mean, what do think about X" to clarify what was the real intention, the only meaning that would make sense to rational people is that the first person asked about the meeting they just left, and the second person used "it" to also refer to the meeting.
Can I ask why you are asking this? What other scenario did someone suggest?
Student or Learner