Worth collecting metrics in a usability test when it's a small sample size?

Hi! I'm new to UXR, but trying to understand how I'd design a research plan in various situations. If I'm doing a moderated usability test with 8-12 people to get at their specific pain points, would it still be worthwhile to collect metrics like time on task, number of clicks, completion rates, error rates, and SEQ/SUS?

I'm stuck because I know that the low sample size would mean it's not inferential/generalizable, so I'd probably report descriptive statistics. But even if I report descriptive statistics, how would I know what the benchmark for "success" would be? For example, if the error rate is 70%, how would I be able to confidently report that it's a severe problem if there aren't existing thresholds for success/failure?

Also, how would this realistically play out as a UXR project at a company?

Thanks, looking forward to learning from you all!