I think any teacher worth their salt can teach English and draw the parallels between modern vernacular. I would like to believe teachers can do both.
I’d even go so far as to call teachers who refuse to adapt to the change in “slang” lazy.
I disagree, I think the slang does convey rich meaning to the correct informal audience.
I would like to believe the slang is important code for another demographic that people can switch to.
As crazy as it may sound, I think depriving or deminishing the slang creates a divide culturally.