Is it a bad idea to make a dating profile stating I want a FWB

Initially I like your straightforwardness and hopefully it'll filter out the "less qualified" candidates.
I say go for it. The worst that will happen is you'll get great practice at saying 'no' or if they're polite 'no thanks'.

I have no experience of dating sites, but I'd be a bit sceptical of men's self assessment of your specifications.

Definitely not a bad idea. I think I just had my profile as “not looking for anything serious” last time. Or it has the option to say “looking for friends”. And three years later here we are but… 😆 it started out as just a lot of hanky panky and brewery nights

that IS the best Idea

There ya go !!

Honesty is the best policy

That’s what 90 percent of guys want anyway. 😃