If this is genuinely the preference of both of them, no. If one is miserable, yes. And if you think sex is only about 'stimulating each other's genitalia', then I am sorry your life has been spend having such unconnected and emotionless sex.
And really, all the tales of ' I know couples who are totally happy and devoted without sex.' How on earth do you know this? Have both partners confided this in you separately? Because if you have not, you have no idea how the other one feels.
The guy I know, I am sure his partner waxes lyrical to her friends about what a wonderful man he is, staying happily and devotedly with her despite her no longer being able to have sex with him. She and they must think the sun shines out of his arse. And they are, from the outside, devoted. The sort of couple who walk to the shops together to buy bread when they run out, spend loads of time together. Best mates.
But to a couple of his close friends (not mutual friends with his partner) he has confided his misery, and his constant dilemma about whether to leave her. And honestly, I think one of the things keeping him with her is he doesn't want to be exposed to their friendship group as not being the devoted, loyal partner they all think he is.
You really do have no idea what both partners in those marriages really think.