This is the correct take. The advice preceded the LLM boom. They were trained on the 'dump them' advice and proceeded to reinforce the take. So why did the relationship advice change dramatically? I speculate attribution to the disinformation campaigns during this time. They were and still are grossly underestimated.
Not sure what sorts of disinformation campaigns you're referring to...
There is something more interesting to consider however; the graph starts to go up in 2013, less than 6 months after the release of Tinder.