10 total days off would be below normal. Usually, vacation time is quoted as an addition on top of normal holidays like Christmas and Thanksgiving and other days.

Average professional job has about 8-9 paid holiday days, plus vacation time on top. My worst number of vacation days was 10 at my first job right out of college (they had to change after they struggled to attract employees) but every other job has been more than that.

But only accounting for 10 unpaid days per year would barely cover minimum federal holidays, so it’s not realistic. It’s equivalent to saying you’re never going to take time off unless the company is shut down for a federal holiday.