A lot depends on how much you’re charging, of course. At our prices, guests expect fresh linens and towels. (I had one couple once who assumed that it was like a hotel and they’d get everything fresh every day!) But even with budget accommodation, cleanliness is important for the guests and equally important for the hosts, if not more so.
Another issue is the bed ‘usage’. This is something that as hosts we have to think about, like it or not. I’m not saying that couples over 70 don’t, but they are possibly likely to have less frequency that a couple in their 20s. It’s a fact (deduced after hundreds if not thousands of guests) that a post-menopausal female will have cleaner sheets than a couple in their twenties or thirties. Sorry but it’s largely the case.
Both our rentals have a queen bed and therefore most of our guests are couples. (Singles happen but are fairly rare). Couples will do in bed what couples do in bed, regardless of age or orientation.
However even people who are not having sex, including single people, can have a scratch that bleeds onto the bed and they still have the full variety of non-sexual bodily fluids.
Personally, I want them washed off my sheets before eleven days are up.
I don’t ask guests if they want a mid-stay clean, linen and towel change, I tell them.