Even if someone's an agnostic or theist (or subscribes to intelligent design), there's still the concept of -- and I forget who coined the sentiment -- "The God of Diminishing Margins", I say sentiment because that may not have been the exact phrase (but it was a person who believed in a creator)
In a nutshell, what their sentiment meant was that for believers over time, the things people can't explain (yet) get put on God & miraculous happenings. As people learn more and more how things work, the less they need to put in the default "God did it" bucket. And that doesn't necessarily have to diminish their belief in a creator, it just means there's one more thing with a naturalistic explanation that doesn't have to be attributed to a supernatural default explanation.
For example, there was a time (pre-modern science) when people simply thought all illness was a punishment attributed to a God. From their limited information and vantage point, all they could observe is that this person who was feeling fine the other day is now very sick.
We now know (and it's not even controversial among deeply religious people) that regardless of your behaviors or faith status, if you walk spend a day in a room with 10 people who have the flu, and you haven't had it yet this season, you're probably gonna get the flu. Much like if you eat a piece of undercooked chicken that's been sitting on a countertop all day, you're going to be having some "digestive discomfort" that's in no way associated to whether or not you committed sin earlier in the day.