Aluminum (?) transformer on new 4k5 and 6k5 models?

In that case, isn’t the copper more appealing?

Then maybe someone could help me understand something…
If you look at the specs and considering the power output, the MP2-4K5 and the MP2-5K have exactly the same power output.
So why will someone will get the MP2-4K5, when the MP2-5K has bigger peak power, bigger charging current, bigger transfer current and wider battery voltage?
More of that, despite what Guy @guystewart said on that video (“with aluminum transformer it’s lighter and it’s cheaper”), the MP2-5K is still cheaper despite it’s copper based… At least here in my country… (4K5 - 1100 euro, 5K - 860 euro)
So?.. Just because it has a slight taller form factor and it’s 8 kilos lighter?