Engineers are problem solvers, and a manager who applies pressure becomes the problem the engineers decide they need to solve. If it is really important to deliver Something™ by the date, engineers will, if enough pressure is applied, deliver unfinished code by that date. Unfinished code that is full of race conditions, performance problems, outright bugs

This is wrong. You can and should deliver "by the date", but you should also prioritize ruthlessly, and ship at least the top of most-important-features list with reasonable quality when time runs out.

Of course, this implies that both managers and engineers have to understand deeply, what value each feature brings, and communicate among themselves and with their client continuously.