It has it's own challenges, sure... but english isn't even remotely close to being the hardest language to learn
The spelling is messed up, it has (like virtually every language) a bunch of exceptions to rules, but the grammar has been hugely simplified over the past 1000 years.
Not to mention that the biggest advantage to learning languages is familiarity and the fact that English is, well, everywhere makes it easier.
Sure Esperanto is easier, but for most of the world something like Japanese would be muuuuuch harder
Doubtful, given that Dendi is Ukrainian...
But now that I think of it, he's a Russian speaking Ukranian so maybe he WOULD be their first choice...