Adoptee here and the child of an adoptee - I am grateful to Ancestry for what it has enabled me to learn about my family.
I have been both a person seeking family and a person 'sought', if that makes sense. I'm on all the sites.
But OP @Arlanymor - gently, there is a reason why people advise caution on this. If you think people are bonkers on this thread, just wait until you encounter some of the genealogy types who basically treat their trees as sacrosanct legal records rather than a hobby. Nothing matters more than their CORRECT DETAILS, not someone's personal relationships or their privacy. It's THEIR TREE, and their absolute right, yada yada.
People seeking information about themselves or their relatives can be very determined (understandably) in pursuit of 'their truth.'
You may find that how you feel about your own privacy shifts over time.
I think you are being a little naive about the possibilities of an unexpected result. It might not be about you but someone close to you, this is often how people have to get answers esp in the UK where fewer people test.
You might consider hiding your matches until you get a feel for the site and the process and what levels of comfort you have.
Good luck - it is enjoyable and I am hoping to crack a longstanding 'brick wall' for my husband.