Telegram changed in the last couple of years. You can choose between secret chats (e2e encrypted) and normal which are just user-server storage-user encrypted. End-to-end voice calls is also a feature. If you ask me between the Google / Facebook messaging apps (Whatsapp, Messenger, etc) and Telegram, today I'd say Telegram has an advantage because it has a good UI, works across devices and the desktop client works like a charm. For someone that wants to ditch the Google / Facebook environment and be sure their grandmother can use it, I don't see much better options.

It's not as faulty as it used to be, but I see the old times made a reputation for it.

I wonder the same. The reason I use Telegram is because it's the only thing I can convince a significant enough number of friends and family to move over to because of the superior user experience and non-Facebook, not because it's the most privacy-friendly solution out there. If I could choose a platform, it would probably be Wire, but the UX is pretty bad and I don't see my mom using that.