Not to mention, the meaning to Celeste in question is nearly identical to both Getting Over It and Dark Souls. All of these games are about, mechanically, I'm not even talking about their narratives, overcoming something difficult. But, only one of them is the author unable to understand.

Since I'm here anyway, it really bothered me that the author claims that Space Invaders has meaning because it has highscores, but never explains what that meaning is. I know what it is, of course, but if I'm being real, I don't think the author does. Look at this quote about Space Invaders:

Even if you’re just playing against yourself, there is a tension of getting farther, doing better, honing your craft and seeing it reflected in concrete terms.

How does this not apply to almost all video games? How does this not apply to Celeste?

This article is not about anything, it is a diary where the author is trying to figure out in real time when it was they lost the spark.

I don't get the author's point really.

I don’t feel like I’m climbing a mountain, I feel like I’m playing through a gauntlet of single screen platform levels.

Those platform levels almost exclusively take you to higher grounds, unless Madeline is stuck in some place for narrative reasons (e.g., the hotel, and even then she's trying to exit it through the roof). There are altitude markers. The map is literally a 3D rendering of the mountain with an obvious progression toward the summit.

Both figuratively and literally, you are climbing that mountain.