That was a weird discussion and I'm still unsure on why Nye thought it was a good idea to do it.
The young-Earth creationist modus operandi is lying, and Mr. Ham tonight, as a spokesperson for the YEC organization Answers in Genesis, exhibited a few primary lies that someone in an actual debate would point out at the earliest convenience.
1. There's a substantial dichotomy between observational and historical sciences. Mr. Ham wants us to believe that the difference between YECs and secular scientists is that they both accept objective observational science and then differ completely when it comes to subjective historical science. From an actual understanding of science, there is no such dichotomy, because all science is subjective to one degree or another. Heisenberg's uncertainty principle doesn't just apply to subatomic particles: we can not objectively know every one thing about a process, an event, or a pattern. That means that both "observational" and "historical" sciences are the same intellectual process: make hypotheses, assemble evidence, test hypotheses, repeat repeat repeat. Mr. Nye eventually sort of covered this topic when he mentioned that astronomy looks into the past, but not very well.
2. Young-Earth creationists get published in secular scientific journals. Mr. Ham included video snippets from Dr. Stuart Burgess and Dr. Danny Faulkner and Dr. Andrew Fabich who (if memory serves) all made this statement. But they, and Ham, very carefully don't say that their publications had anything to do with YEC perspectives. That's a bait and switch. YECs get published in secular journals wherein they don't discuss YEC beliefs, whereas the only journals that publish YEC beliefs demand religious purity of their contributors. Mr. Nye in no way discussed this.
3. YECs believe in a lawful and orderly universe. Mr. Ham made this claim multiple times, while arguing that a lawful universe requires a creator. But YECs do not believe in a lawful universe. Mr. Nye attempted to point out, although not very thoroughly and somewhat confusingly, that the YEC worldview has three chaotic, universe-changing events: the creation week, the Fall, and the Flood. YECs support uniformitarian rates of events at all times except during those three events, when things acted in magical and scientifically irreplicable manners. There is no way to run an experiment on what happened during the Flood: it was a cosmic unique event.
Overall that livestreamed 'discussion' was distressing. Two non-scientists stood in front of a crowd to discuss whether something was scientifically viable. That's not very sensible.