Let me take you back on that Kpop 101 history current gen fans desperately need.
Kpop has ALWAYS BEEN WESTERNIZED from it's very conception. It is a hybrid of MoTown and Johnnys mixed with Konglish and highlighted with intricate choreography and weird fashion. It has it's unique flare because of the combining of all the things mentioned above but it now has been elevated globally more than it's ever been because of BTS. But why are BTS the only one being labelled as "sellouts" "too westernized" so far? Surely it can't be because they succeeded at what kpop companies have been trying so desperately to do since 2002?
Here's where the history lesson come in. I joined kpop through Arashi in 2006. Think it was SS501 on Music Japan that got me curious and the rest is history. But the focus that I've seen has ALWAYS been for global expansion. So much so that the term "hallyu" was coined to be South Korea's soft power. And funny enough it was their kdramas that was initially spreading the hallyu wave. Back to kpop however, people have this notion that English songs/western focus or expansion is a recent concept. It's not.
BoA was THE FIRST ACT to seriously attempt MULTIPLE TIMES to enter the US market since 2002
Then she attempted again and failed with a whole English album containing more than 10 songs, 3 she made promotional MVs for
The whole English album
She was the one who really overplayed her hand after seeing the success she saw in Japan. She has more English versions of songs that you can find if you curious. She REALLY TRIED.
Next,
Se7en, who used to be a YG act, also released an English single, that was FAR too early for the kpop industry but that didn't stop the big 3 from trying
He released other English versions but unlike BoA he took that L and never did it again as far as my memory remembers.
Enter to the ring a new contender that actually did decent for the time it was released but still the foreign markets weren't ready for kpop. Nobody English Ver by Wonder Girls.
Also the first to perform on an American day time talk show
It was the first kpop song to enter BB HOT 100 but then quickly fizzled out. But that did not stop JYP after seeing his group doing something BoA or Se7en couldn't do.
And that's where the "curse" or narrative that kpop acts will fail started that even JYP had to admit himself was because of his sad attempts at the US industry and him self sabotaging his own group domestic popularity.
But kpop attempts didn't stop with just the big 3 from 2002-2009. 2010 saw the official split of JYJ and 2VXQ. And JYJ, just like the big 3 mentality that preceded them, thought they can crack the US industry releasing this travesty.
And it's English album
TL;DR
Point is I can list many more groups in 2nd gen and 3rd gen that have released more than 3 English songs and English albums vying for "western validation" and have always prioritized the "hallyu" wave going global but the buck always stop at BTS doors because unlike the many failures before them, they're the only ones to succeed in doing what kpop has been trying to do since it's birth. But somehow BTS and them alone get the stigma of being "sellouts" for releasing just 3 English singles.