The "formula" you're citing originated with classical drama, I suspect (Aristotle's Poetics; the French notion of "unity of action"). Today, it's reinforced by the modern descendants of ancient drama: Hollywood screenplays. Hence the common demand that a novel have a three-act structure with a midpoint, basically following screenplay manuals.
(ETA: The happy ending, however, is totally optional. That's only ever been a "requirement" in particular genres, like classical comedy and much romance. It's commercial, but it's hardly universal.)
There's nothing wrong with this structure. It's lasted thousands of years (with many variations) because it works. In a two-hour film or three-hour play, economy and unity are paramount, and such formulas help writers root out rambling subplots and the like. They can be helpful for many types of novel, especially anything where suspense is important. I use three-act structure myself.
However, the novel, from its very inception, has offered many other possibilities, including long, rambling, branching narratives and forms of parody and experimentation that turn the dramatic formulas on their heads (Don Quijote, Tristram Shandy, etc.). Many postmodern novelists have taken their cue from those early weirdnesses.
Some novels were serialized (like Dickens') and arguably offer no more of a traditional dramatic structure than a typical serialized TV show does today. Others were epistolary, like Pamela or Les Liaisons dangereuses — what we might now call novels composed of "found" material. Others were first-person narratives that masqueraded as memoirs, and so forth.
I'm sure a critic could argue that, at their root, all novels follow a version of the formula you cited. It's hard to have a compelling novel without some form of protagonist(s) and some form of conflict. But within those parameters, there are an unimaginable number of possibilities.
But, rather than getting hung up on formula, I would simply ask whether the novel has enough conflict to keep someone reading. Don Quijote is rambling and digressive, but the basic conflict of delusional dude versus reality is compelling. I look at a lot of self-published literary novels, and I would say the No. 1 problem that makes me put them down is that the author is way more interested in exploring a world-view or a voice than in creating conflict. Chapters and chapters of introspection work if you are Virginia Woolf, but rare is the writer who knows how to make "a character sitting around thinking" compelling, in my experience.