I do think that things like emojis and the (now fixed) link previews do help with adoption. But I think there is another and more compelling adoption method given the current state of the world: privacy and security. The reason people are turning to telegram is because they think it is secure. Signal will never gain mass adoption without good groups. And honestly, they probably need channels too. If it had both those things then all these protestors would turn towards Signal. After all, isn't that why they get funding from the US government? To "enable" democracy in other countries?