Not only the idea that Tinder is majority used for hook-ups, but the idea that people have been having casual hook ups for hundreds or thousands of years, and mostly falling in love through work or long term social relationships. You don't have to look very far in time or geography to see societies that don't work anything like that. Arranged marriages, gender segregated schooling, lack of women in the workplace until relatively recently.
And FWIW, within my social circles, Tinder is frequently used to find serious (as opposed to casual) dates. I have just moved in with my girlfriend who I met on Tinder.
It's baseless and directly contradicts the data in the article, with no evidence outside of a personal experience with Tinder.
This is the most aggravating thing, even beyond the content of his comment and the way that it implicitly insults people who are trying to use Tinder for more than hookups: people see an app/phenomenon like Tinder and make a quick simplistic judgement based on what they want to see and their moral biases, and then make sweeping pronouncements like that.
And further to the point, his observation does not change if you find and replace 'tinder' with whatever app you DO use for hooking up.