They have had two apps (Telegram vs Telegram Desktop) on macOS too for a while. IIRC one is Electron-ish-based and the other is native Cocoa. The first one got features slightly faster but lacked Secret Chats IIRC.
Explains why it doesn't take a minute to start and doesn't need a gigabyte of memory.
The effort that went into that thing is amazing. It's fast on my 5 years old Pentium.