I am enjoying great times in my life being single and having a couple of FWBs - in fact I am "grooming" a third one (in another current thread if you are curious). A couple of years ago I had a fantastic FWBs whom I met in a Facebook group, started talking, became friends and it was clear there was a strong sexual attraction. Best sex of my life! I ended up falling in love with him (the first time this happens for me), but after going no-contact and taking 3 times to sort out my feelings, now we are friends again (with occasional benefits still, the sex is too good to completely cut it off!).
I have another FWBs who I met more recently on Tinder... he is really hot, VERY good looking, a happy and positive person, in a messy separation circumstance so he does not want to get into any commitment relationship, which suits me very well. Intellectually he is not at my same level and this is crucial for me in order to consider someone "relationship material", so no risk of feelings getting involved there. We see each others as friends, to talk, go to the movies or going hiking, and often there is sex, but not always.
I have very recently started exchanging spicy messages with a guy who was friend only, but he is also very handsome so I wouldn't mind upgrading him to FWBs. This is in the other thread I mentioned, and in some of the comments you can see the reaction of other women to having an arrangement like this... there are still a lot of assumptions and judgement towards women who have several sexual partners with no intention of having a conventional relationship with any of them. But these are other people's issues, not mine, so I let them have them. i don't want them.
Yes, you can fall in love with a FWB, but you can also fall for a platonic friend, or a stranger you just met, or a workmate, or your DC's teacher. That does not mean having FWBs is not great!