And the journalist who gets paid to write a nice article about Signal will surely get a quote from the protestor who happened to use Signal and not Telegram.
I'm far from being Telegram fan considering their custom crypto, lack of E2E by default, etc. Yet NEXTa channel here actually have 2 million of subscribers while Belarus population is less than 10 millions. Yeah of course there some % of people from abroad who follow the situation, but it's still a lot.
Also Telegram was more-or-less resistant to at least not leak any personal information of their users in ex-USSR. So it's works well enough for protesters threat model.
I'm not sure why you've brought up Signal, they're completely different platforms.
Signal focuses on secure communication, Telegram has a secure communication feature... But also a social network of group chats and channels that link to each other; and that's the focus of this article.
It was just an example of a product which could be touted as enabling protestors.
The other use cases of Telegram could be serviced by other apps. There are plenty of non-E2E social networks available just like Telegram.
EDIT: Unfortunately postmodernbrute I am not able to reply to your comment. But I am not trying to deny that Telegram has caught a wave of popularity among Belarusians and others. What I am saying is that Telegram likely only has that trust because of puff pieces like this. It is not because of any technological superiority or unique feature that it provides (since it isn't/there aren't any).
But there wasn't another communication tool that was similarly popular and trusted among the Belarus people. And that, is the difference. Their choice in this protest matters much more to the reporting than your opinion as an outsider.
Also Telegram was more-or-less resistant to at least not leak any personal information of their users in ex-USSR. So it's works well enough for protesters threat model.