The reason medicine does double blinded research trials is because drugs can do a massive amount of damage which is not necessarily immediately obvious.
A parachute does no damage.
My understanding of the cass review is that six of the seven adult units refused to release their data so there is in fact very little observational data either.
The medical profession has as it's guiding principle first do no harm so if there is suspicion the drugs or intervention harm people they should be carefully assessing the balance of risk and reward.
This has been applied to opioids and many many other drugs.