I fully understand the argument and kinda agree. That said, here’s why i still use the Telegram self-chat just like OP, you can suggest a note-taking app replacement if you think:

• Paste a link, instant preview of it without user intervention, can play it right on the app if it’s audio/video if i want or get a preview of it if it’s just a page without opening a full browser (this puts it automatically above a “synced notepad” which is what i understand note taking apps tend to be)
• Synced across devices
• Both desktop and mobile
• Private, no one else sees it
• Easy and convenient, i usually have Telegram running already, just switch to it on browser or desktop and copy or paste the thing

Gimme a note taking app that has all these, that is not a big program needing lots of resources to run all the time, and that i can self-host for the server part (or E2EE P2P like Syncthing) and we’re cooking!

Since i use the self-chat on Telegram a lot i’ve wished for exactly the same thing in the past as i’m planning on leaving the service, so far haven’t found a right fit yet