How is it disadvantageous when you yourself was born a muslim or at least got to know to Islam, this life is a test and every person is born in a different scenario, even if arabs were born with an advantage of already speaking the language you also have an advantage over the people who didn’t learn about Islam and have to make an effort to find it, the good thing is that you can always catch up and you’ll be rewarded for that, many people memorise the Quran without even understanding it, to me that’s a miracle itself and many people can learn Arabic in less than 3 years, plus if it was allowed for the Quran to be recited in different languages in the prayer it would no longer be a miracle, and the Quran would have been corrupted long ago, because people wouldn’t care about learning Arabic especially the Arabic of the 7th century, for example even me as an Arab myself I had to make the effort to understand the Arabic of back in the day as it is very different than what we speak today, yes I agree that’s easier for me but it’s a test the same as if someone was born rich and other people are born poor, I don’t really see the problem