Thank you for having posted this, very interesting dialogue:
• what they say about the lack of noise makes sense. Personally, I really like the vibrations and noise of 4 strokes at races, but just like they said there have been very very intense moments in other kind of sports like basketball in which the only noise that you can hear is the crowd; I guess that the only way to know is to put the best riders on electric dirtbikes and see the reaction of people.
• I do agree about the fact that the internal combustion engine has almost reached its limits and it only improves a little, while the electric motor and battery technology, which is already comparable if not superior talking about performance, looks like it's still improving fast and like it's far from having used its whole potential.
• What they say about lithium mining is, I think, a very difficult topic to discuss because there are so many things to consider that IMO not even the best experts in the World can answer the question: "is going all electric overall more environmentally friendly than using ICEs?".
Here is my opinion, though. Nobody cares about the impact of lithium mining for smartphones battery because, I guess, it's negligible. People do care about mining for cars battery. A motocross bike has a way smaller battery than a car and even if, thanks to the advantages of electric motors, more people will get involved into dirtbikes, I estimte that dirtbiking will still have a negligible impact.
I am also aware of the fact that my opinion about it is unreliable and that probably nobody has a sure answer.
BTW, if you'd like to learn about climate change, I can suggest the videos from #15 to #21 of
this playlist. If you have a high school diploma you can certainly understand what he says: he starts from the basics and then moves to interesting knowledge.