These munitions were anti-runway munitions which had to be released over the runway, flying straight and level. The Tornado crews didn't fancy their chances with such a weapon.https://en.wikipedia.org/wiki/JP233
Deployment was rather frightening for the flight crew, since it required the aircraft to fly low, straight and level over an enemy airfield, and when over the runway the pods would dispense their payload. During the Gulf War it was widely reported in the popular press that Tornados were shot down by AAA fire and MANPADS during delivery of the JP233 munition, but in fact none of the losses occurred during the attack phase of a JP233 mission. Only one aircraft was lost carrying the JP233 munition when Tornado ZA392 crashed into the ground approximately 16 km (10 mi) after delivering the weapon at low level; enemy fire was not reported and it was believed that this was an incident of controlled flight into terrain.
What alarmed the crews of British and Saudi Arabian Tornados using JP233 was that the aircraft was brightly illuminated at night by the exploding munitions. Attacks using JP233 were suspended six days into the Gulf War, as the Iraqi Air Force was effectively flying no missions.
With the increasing availability of standoff attack munitions capable of the same mission with little risk to the flight crew and aircraft, and the British entry into the Land Mines Treaty (which declares the HB-876 illegal), the JP233 has been withdrawn from service.
Instead, release steerable munitions at medium altitude which guide themselves to specific points on the runway.
Low level attack to approach the target is fine (radar avoidance) but on reaching moving to medium alt to get better time to respond to threats may actually be better, deploy munitions and then again get to low level to run off. Lo-Hi-Lo.
USAF crews in ODS faced similar issues. Got, trained on LANTIRN (basically optics + TFR for low flying) then went to their bosses and asked for medium alt attack clearance because of risks involved.