If this is the choice you've made, then Oral with protection IS the right thing for you to do. If you are not comfortable offering it, don't offer it period- If other WG's are doing it and men are asking for it, tough. You can't let your boundaries on your health and safety be influenced by what other people are doing in this work, it's not their body it's yours, and it's your peace of mind. If you want to offer OWO go for it, but you needn't do something just because other people are :)You might lose some business, but you might gain some too, and those you gain may be those more appreciative of your boundaries and better clients for it.
I searched AW for my area, and a lot of girls are offering bareback sex- And I have been asked for it, but this is something I would never do- so I say no. I wouldn't offer it EVEN if it was industry norm and I was the odd one out. It's sort of similar.
If they ask for it just say you don't, and justify your reasons too- It's better for both of you: If you had gonorrhea or herpes he could get that through oral, and then have to explain it to his wife or partner where he got those sores and warts or what these antibiotics are for. (I reckon pointing that out may shut some mouths) Similarly you can get it from giving oral without also. It saves him a lot of explaining and stress AND health, and it saves your health and everything else besides.
And if you aren't comfortable giving it, then every time you do give OWO more likely than not it'll be planting worry in your mind, and you'll hate doing something you don't want to that crosses your chosen boundary. I'm willing to bet some men would appreciate this- Just as they wouldn't want someone who has unprotected penetration so they may appreciate a girl who is putting full safety first.
Sorry** Didn't mean to shout/lecture you hope I haven't, just it's quite clear you've made a choice for yourself and are feeling pressured to change it, and I wanted to do some cheerleading xx