I teach Secondary RS and I definitely agree with this: "Not so RS, you have to be prepared to be bottom of the pile."
In many schools these days, since progress 8 came in, schools are ditching short course, and unless you're a religious school, schools are increasingly dropping compulsory GCSE too. In my local area partnership (of 7 secondary schools) none will have compulsory RE in Sept, and only one doing short course. The rest core (non examined) and options.
So, yes you can have a lot of kids who don't like it, and a lot of parents who don't see the point either. "We're not going to bother with RE" type attitude. Of course that has its benefits, when it comes to open evening. Unfortunately though, in all too many schools SLT have that attitude too. You therefore have to make the kids engage, with good teaching, an interesting scheme of work etc...
But one point to note, people often talk of doing "philosophy and ethics". There's no such thing! Schools often like to name their subjects this to make it more attractive to students, but the exam at A level is either Religious Studies or Philosophy. Philosophy is great A level, but requires students to study epistemology. Religious Studies requires students to now study 3 of four options (philosophy, ethics, world religion or biblical text). So if you teach RS at A level, 1/3 of your time will be spent teaching a religion. The only other option is the pre u which offers philosophy and theology.
Happy to answer any other questions.