I find it difficult to discuss productively when you come up with such overblown analogies like that. I could even argue that artistically there could be merit to the equivalent a book full of thumbtacks, and Fear & Hunger comes to mind as a game to be described like that, One where a myriad ways to suffer is central to the experience and themes. But to say that Hellblade is like that is so uncalled for it makes that whole angle of discussion pointless.
You may have written about what a game is and if it has to be fun, but you are not staying true to what you preach. You can't even seem to acknowledge merits in games that you are not personally entertained by.
To judge Hellblade for being linear is several decades too late to start that argument, and there is no reason to single it out. Loosely half of all games today are games where you perform as expected in a predefined context where your choices don't matter, but most people still think of them as games. What was the benefit of that semantic argument then?
And even if you were to say that Hellblade, like Spec Ops The Line, is more like a "theme park ride" than a "game", to compare it to "a book full of thumbtacks" says absolutely nothing about how it's constructed and what may be issues in that. It just says that you really, really don't like it. If that's what you have to say, then there is no point in even talking about it. I can acknowledge that you don't like it and that's it.