Honestly, At times resigning is better, particularly if both players are high elo and know about things Like stalemate threats, Checkmate threats etc, There is almost no use in continuing playing, Unless you spot a crazy tactic before resignation.
It's true you should never resign
I resigned against a GM when I had a betyer position. Forgot I was taking back with check gaining a move. So yeah. Always play your best to the death. It shows emotional resilience.
I though I had my opponent, but he completely flattened me in the end-game, it was impressive!
You probably linked the wrong game. In the game shown, nothing of that sort happened.
This is probably my worst decision to resign - I look back and just don't know what I was thinking! Probably something along the lines of 'Oh no, I've lost my queen. Yes, can't do anything about that at all - I'm in check and my queen is hit. Blocking with the bishops is no good - I just lose my queen. Yep, my queen is absolutely lost and there's nothing I can do about it - where's the resign button'. Idiot.
Yes , sometimes you can even win from a completely lost Position . And it Holds true for Almost All Levels unless you are an Super GM . Have a look how one of my games went from completely lost to won .
https://youtube.com/shorts/j6bXpJ2ScB8
I was at an event and a 14 year old 1800 was completely lost against a master but he kept playing on. Disgusted about opponent not resigning so could move on to the next round which was soon to start he then just started promoting his pawns into knights. After the 4th knight promotion the kid got that he was being disrespected in return and resigned.
I though I had my opponent, but he completely flattened me in the end-game, it was impressive!