How important is it to replace front and/or rear struts? Is it a safety issue; or, merely a matter of ride comfort?
If they are genuinely worn, then this is most definitely a safety issue.
When your struts are worn out, your wheels bounce excessively and uncontrollably when you hit a bump in the road. Each time that the wheels bounce like this, they lose some of their contact with the road, thus leading to poor road-holding and to uneven tire wear.
I’m curious about how many miles you have on the odometer of this Outback of unknown vintage. My '02 Outback, with ~105k on the odometer, gives no indication of needing new struts. My '97 Outback also did not need strut replacement during the time that I owned it.
How old is this car, and how many miles are on the odometer?
Do you normally drive on roads that are in very bad condition?
It is a 2002 with 111,000 miles. We do drive on unpaved roads some; but not often. I estimate we drive about 500 miles/year on unpaved roads.
I have not noticed any uneven tire wear.
The reason I suspect it needs struts is it seems to ride rough on bumps as compared with the past.
I am the first owner.
I agree with VDC. Given your use and miles, it almost certainly needs 4 new ones, assuming you want to keep it a while. They wear gradually, by the time you notice it they’re usually quite worn.
111,000 miles I would be very surprised if it did not need new struts.