That Human Rights exists and can be incompatible with other law. It says so in the Human Rights Act
Again that is not how the Human Rights Act works - it's worth reading.
https://www.legislation.gov.uk/ukpga/1998/42/contents
Your argument seems to be that something cannot pass in to law if it is incompatible with the Human Rights Act. This is not true.
Anything that increases the cost and risk of failure is going to work as a deterrent. Even if just 1 in 20.
We have record numbers crossing, we are on track for 50,000 this year.