I do agree that It's difficult.
Because whatever the dodgy practices and breaches, our government has, passed laws against fox hunting and ear docking as a reflection of what society believes is right. So legally, we have banned fox hunting, just as we have banned burglary, and speeding and everything else that is against the law.
If we don't have a law against cutting bits of children's bodies then we are surely condoning it?
Smoking weed reputedly causes fewer health issues than alcohol, yet it's illegality is arguably behind gang-related violence, county lines, modern slavery etc etc - so yes, there are big risks in potentially deflecting to an illegal trade as an alternative to legal.
And without legalised abortion we know that a return to back street practice would cause untold damage.
The law (in circumcision being allowed, and in unregulated circumstances) around this just seems so incongruent with every other law about abuse and assault etc. Cut off a foreskin: fine. Cut off an earlobe: Criminal.
On balance I would be in favour of making it illegal and would vote that way in a referendum, for example.
Apart from anything else, what else might be allowed on the basis that it is a religious practice?