Lots of schools don’t offer the SAT IIs at their school. That isn’t a good reason to skip it. I’d say if they are offered within a 3 hour drive and you aren’t really low income, do it.
Be strategic about which ones to take, though. I’ve seen a lot of kids crash on bio —maybe because so many kids take it, and also many have had AP bio. For STEM kids, it seems like Math II is the easiest to study for and get a very high score. Math I is a waste of time, schools round rather see Math II. My kids are lifelong readers, and found Lit pretty easy with minimal prep. My kid who likes history actually enjoyed studying for World History.
Also, not every subject is offered every date, so be sure to check that.