Personally, I'd say a game feels like "hand holding" when there's no room for player agency. The key thing that sets video games aside as a medium is interactivity (as a two-way relationship) and player expression, and I think when a game is referred to as "hand holding", it's because there's little-to-no room for players to express themselves - no obstacles to find creative solutions to, no way to play the game/section in different styles, etc.
I think the only real examples of "good" hand holding that spring to mind are optional tutorial sections where the player has specifically requested to be introduced to certain mechanics.
And there are absolutely games that aren't handholdy enough, too - where players are just thrown in at the deep end without any explanation for what's going on or how to play. Sometimes the lack of direction can be a good thing - exploration (of both a game's world and its systems) can be exciting and rewarding, like discovering for yourself how to survive and advance in a survival game - but some games are so complex and overwhelming that players not being introduced to things more gradually can be really off-putting.
It's difficult to say where I'd draw the line, though; I think it's a somewhat personal thing and something that varies from game to game. Quite a few of the games I enjoy, such as Path Of Exile, are far too overwhelming for the "average person". And a lot of "cinematic third-person action adventure" games (like the majority of Sony's first-party titles) feel overly-restrictive to me, like I'm just being railroaded without really having to engage my brain much and without really being able to express myself through the gameplay. But the window of "handholdyness" that's appropriate for me is wildly different to the average person, who does enjoy Sony games and probably doesn't enjoy Path Of Exile.
I think this also somewhat ties into the idea of accessibility versus depth. The more handholdy a game is, the more accessible it is. But making a game accessible quite often involves removing the intricacies and complexities that result in mechanical/systematic depth. Is it possible for a game to have incredible depth, complexity and variety while also being intuitive and accessible for a brand nee player?