10k miles ran up in less than 6 months backed up with OEM recommendations isn't crazy at all.
That's likely only around 300 hours or less depending on how they're used. I've cut open plenty of 300 to 400hr filters and found almost nothing.
I've got one little 15L diesel that recommends 1,500hr oil changes, if that many hours can be put on there in less than 6 months. Longest I've seen one of those go for was 1,300hrs over 2 or 3 years. I would not recommend doing that. The 2 engines I've seen that had problems likely from the oil not being changed had over 2000 and 3000 hours on them.
API and oil company testing using hours isn't me making assumptions.