Well, wouldn't it be similarly true that if it does take twice as much effort, and the advice is asked for and received online, that the person receiving or offering the advice is sufficiently more likely to spend that time not in those spaces?
Put another way, if it's twice as hard to meet someone in real life, couldn't it be because the single person is spending twice as much time away from real life, and their potential targets are doing the same, and subsequently wondering why it's so hard to meet people there?
Pretty hard to meet someone at the gym if you're spending all your time on Reddit asking for dating advice, and the rest in the bathroom swiping through tinder, meanwhile when you finally sign up you spend all your time with headphones on looking unapproachable.
If someone asked for my advice in the dating world, it sure as hell wouldn't be "spend more time on the Internet, and relationships will happen" despite this shitty chart indicating that's how some percentage of recent couples have met