Why the template still helps, even though it looks trivial
"As a [role], I want [goal], so that [benefit]" is the most recognizable format in agile, and also the easiest to write badly - a story that's technically in the format but reads like "As a developer, I want to refactor the auth module" has a role and a goal but no real benefit, which is usually the sign the work needs re-framing around a user, not a task.
What the INVEST checklist catches
INVEST (Independent, Negotiable, Valuable, Estimable, Small, Testable) is the standard sanity check for a drafted story. Running your draft against all six catches the most common failure modes: a story that can't be estimated yet (missing context), one that's actually two stories wearing one title (not Small), or one where nobody can say what "done" looks like (not Testable).
Using the result
Treat the generated sentence as a draft to refine, not a final artifact - the real value of the format is forcing you to name a real user and a real reason, which a ticket titled "improve checkout" never does.