1. It's not imperative, for the reasons you mentioned - but yes, it still matters. Pretty much no woman on the planet would consider 183cm a dealbreaker, but I'm pretty sure 90% of women would prefer 190cm+ if they had the opportunity.
2. Fair point
3. Whiteness and white models are also heavily fetishized in Asian countries. There are barely any dark models in India and China, and people in South + East Asia use whitening creams to "appear more beautiful", in their own words. Not saying they are right or wrong btw, but it is definitely not limited to white countries.
4. Only girls with shitty upbringings prefer black guys. Probably about 1 in 50 white girls in Finland have ever slept with, let alone are dating a black man - and that is an extremely generous estimate. The number will inevitably be higher in other less white countries, but it will still be a clear minority.
5. He is *mostly* right, according to data collected on the topic. Tall, lanky Africans generally on average have slightly bigger penis sizes than the North European average, but the shorter/stockier Africans do not. Either way, North European countries (+ some South European countries) are comparable to African sizes. Obviously I am just going based on data online though, and it could be wrong.
6. You are both correct.