Stories, either written or on film, get boring when logic dictates what does and does not happen. We don't empathise with logic, we empathise with the human elements of choice, namely strong emotions.
We see someone cry, we get upset. We see someone kills the dog left to you as a gift from your dying wife (John Wick plot)-- just fuck 'em up mate. All of 'em. Now. Go.... and then we get pulled along as the story kicks in, learning more about the world.
I have come to realise that the decision I originally set up is a win-win situation for the protagonist – there is a downside to the decision, but it's not personal to the protagonist, which drains out the tension and makes the protagonist's choice too easy.
I recall the phrase, "If there's something wrong with the third act, it's really with the first act."
- The decision I originally set up is a win-win for the protag
That's where your "first act" problem is; this is relevant to short stories too, the advice is targetted to the telling of a story no matter it's length. Don't show the reader logic, show them emotion. Show them the character MUST commit to an action --any action--.
The decision you speak of, is there any conflict you can introduce that makes it -seemingly- impossible? Any further obstacle the protag must get through so he can commit to the Decision? Why is it your protag who has to make the decision in any case? If the decision is in itself mundane we'd wonder why no one else thought of that, especially as you said it makes the choice easy?
We want to read about Bjorn StrongMoral. He's a curious character thrust into XYZ circumstances (conflict arises). The stakes --somehow-- become personal: he MUST do X or else Y or even Z could happen! But Mr StrongMoral cannot even do X, he must suffer lowercase y's and z's even to achieve it, but by jove he does and at great cost God rest him... Good old Bjorn StrongMoral etc etc...
Just try to enthuse asense of urgency and agency so we know where we're going, why we're going that, and what the stakes are if we don't make it. But THIS is the story about the guy that did...
- There is a downside... but it's not personal to the protag.
There are instances of characters being more observer than operator within conflicts, however in my experience they tend to be more philosophical, using the conflict(s) as a means to introduce new introspective concepts. If it's not personal to the protag, maybe you have the wrong protagonist for this particular conflict, can you change it to anyone else?
Maybe you need to elevate the level at which the story operates; instead of a drama whose impact affects only a village, it will impact millions of lives and cause irrecoverable harm.
3....and makes the protagonist's choice too easy.
That prospect does not make for a rivetting story. However, it may be that you are underestimating your story. Try getting a beta-reader or pay someone to edit your work. They may be able to spot glaring mistakes. When they're done ask them questions for further feedback?
Good luck.