You are correct. This is an old problem to which NASA failed to take corrective action. The engines need to be slowly cooled prior to launch so the sudden onrush of massive amounts of liquid hydrogen don’t damage parts from thermal shock. The bleed system and associated valves failed to deliver enough hydrogen to place the engine’s temperature in a “go” range. In 2021, the launch team pressurized the hydrogen tank to force enough through to continue testing. The working theory was the line was prone to forming hydrogen vapor. Apparently the root cause was not dealth with. All it takes is one guy in charge to theorize without proof to signal an ok to ignore. Thus the engineers who know better get overruled. Very similar to Challenger.