all languages borrow equally easily
Japanese is famously bad at loanwords. Compare アイスクリム (aisukurimu) to coup de gras or schadenfreude. English's loanword game is leagues ahead.
English is still very much a Germanic langauge in grammar and core vocabulary
Yeah, cause of those good old Angles and Saxons who colonised England and brought along their weird foreign words. I have a feeling your "most common native words" are just words that have been in English for a few thousand years. I'm talking about a longer timescale, here. Look at this source which contradicts yours:
https://en.wikipedia.org/wiki/List_of_English_words_of_Brittonic_origin
Few English words are definitively known to come directly from Brittonic, the language of the Celtic inhabitants of Britain prior to the Anglo-Saxon settlement of Britain.
Your claim that English is mostly made up of native words is true if we consider Britons, Gauls, Romans, Angles, and Saxons living in England to all be one culture. And by 1066, they sure had become a single culture. But it's a very silly way to argue against My point that nearly all of the language comes from foreigners integrating their own languages with that of the last batch of settlers. It's very "card says moops", if you know that reference.
Anyway, as a native English speaker, your life gets a lot easier when you bother to pay attention to all the foreign languages you use on a daily basis. If you pay attention to the Latin and Greek we use all the time, then you probably know what the word "aquectomy" means, even though I just made it up. You probably know it's a similar procedure to exsanguination, which is another word you'd be able to guess the meaning of if you pay attention in school. And if you're a law student, you'll ipso facto be using even more Latin.
And even the most dull-minded Anglos pick up at least the basics. Look at JK Rowling, she's a grown woman with the mind of an 11 year old private school bully, but she still filled her books with fake latin that her kid readers could understand. That's English for you, the kids are all multilingual.