Not all those ends are as dead as they look
Some of those dead ends lead to new content which helps establish the feeling something strange is going on, that time isn't strictly linear in this story, and that something else is somehow in control.
For example, when Stefan first arrives at Tuckersoft, Colin's code encounters a bug (what was it again? A buffer overflow caused by some kind of sprite?). From there, everyone goes into Mohan's office and Stefan presents Bandersnatch (game). Neither Colin nor Mohan have heard of the book.
Then, Mohan asks if you want to work with Tuckersoft. If you select "Yes", you immediately run into an ending where Stefan releases the game, it's buggy and half-finished, and a terrible game. Then you encounter what you've described as a dead end. The movie prompts you to go back to your last decision and try again.
BUT! This "second" time Stefan arrives at Tuckersoft, things go a little differently. This time, when Colin's game breaks, Stefan cuts Colin off and explains the bug he runs into. Further, inside Mohan's office, both Colin and Mohan know all about Bandersnatch (book). This shows the viewer that although you're repeating the major events, your choices have a lasting effect on the Bandersnatch (tv show) world. Colin even breaks the fourth wall on this during his acid trip (a few other places as well), and is so confident of it he's happy to jump off a building to demonstrate.
Further, some future options change based on the decisions you've made in the past. In the answer you linked to, you'll see you can pick up some "qualities" along the way, which affect the options you have. It's possible to encounter an apparent dead end, only to realize you unlocked another path along the way. For example, you can go back in time and find Stefan's rabbit as a child, but only if you've talked about Stefan's mom.
Then, of course, from a game perspective (because Bandersnatch lands somewhere between game and TV), every choice can't be equally as significant or correct. That's bad game design. You can see a couple of places where they thought about this: the non-consequential choices at the beginning show the viewer how choices work; selecting "yes" at Tuckersoft makes sense, so most viewers are immediately shown how they can go back and change a choice (and how that affects the story). So dead ends are a little necessary if you want the viewer to feel like they need to put effort into their decisions.