Then almost any blatant lie would be gaslighting, which I don’t think fits the meaning. My understanding is there are more necessary attributes for a situation to be “gaslighting”, mainly the manipulation and dependency.

If someone lies about what they said in writing (in the age of internet archive of all things) it’s just a plain lie, and a dumb one at that.

How is that not just lying?

Gaslighting (if my understanding is correct) is manipulating someone. Making someone question their own sanity, blaming them, isolating from other people and making them dependent on you.

Lying on the internet to win a stupid argument with a stranger hardly can even start to measure to that.

I have never seen an online discussion where gaslighting was used. People usually just learned the term and they think it’s a synonym for lying.