It is a trend, exactly that. Because all major news outlets in the Netherlands are reporting on the Whatsapp downtime, they try to add some perspective with the Facebook buy and poke Telegram. This results in people checking out Telegram as the new trendy thing. Let us say 4/10 contacts use Telegram now. Why bother if 60% of your interaction is still on Whatsapp? Unless everybody switches it will just be a novelty app.