Well... I have heard that Pentagon got backlash when they were singing a cover of BLACKPINK's "Lovesick Girls" and changed it to "Lovesick Boys".
Meanwhile ONEUS got praised for keeping the "Girls" when they were covering it.
And then there is when I was listening to the boygroup Catch The Young singing a cover of Ariana Grande's "Santa Tell Me", and they changed the "he" to "she" in the part that goes "don't make me fall in love again if he won't be here this year".
And I saw one comment where someone was not that happy about that.
Well... I kinda understand that backlash, even though...
But then I'm also reminded of when an Australian male X-Factor contestant was covering Katy Perry's "I Kissed a Girl" and some parts were changed to "I hope my girlfriend don't mind it". But it was still a girl that he was kissing.
So, the song was like "I kissed some girl, who wasn't my girlfriend, but I hope my girlfriend doesn't mind."
And yes, it is not unusual for singers to change the genders of a song, when covering a hetero love song sung by the opposite gender.
I used to do that too, sometimes when singing karaoke or singing a cover of a song.
Well... I remember when Seonghwa covered Troye Sivan's "Angel Baby" and didn't change the "give him my all when I don't even have it" part.
I don't think I saw any comments praising him for that, even though I wouldn't be surprised about those comments existing.
I haven't said everything that I want to say in this thread, but I might add more things.