> The faster you are traveling (which really matters as a factor of the drag you are experiencing), the more serious any event is which changes the shape of your vehicle. Even non structural failures, such as an engine cowling coming off mid-flight can strike other parts of the aircraft, resulting in damage and changes to the structure.
Yes, an engine falling off will be more impactful to a plane traveling at supersonic speeds. But these types of incidents are an extremely minor fraction of overall failures, and particularly during cruise at altitude (e.g., when the risk of bird strikes is minimal).
Engineering steps can be taken to minimize risks like this further since the consequences of failure are higher.
> Commercial aircraft are just impractical to operate safely at such high speeds.
This argument was made when the first jetliners were being rolled out too. It carries about as much weight now as it did then.
> Faster, heavier aircraft need longer runways to land. That limits your alternate landing choices. Diversions may cost you more fuel since they may be much greater distances away.
This hasn't stopped faster, heavier aircraft from becoming commercial successes so far.
A diversion is already extremely expensive for a myriad of reasons. Schedules, aircrew, and sometimes planes have to be shuffled around. Stranded passengers often need accommodation and/or alternative transport arranged. Airfare credits are often handed out. Incurring slightly higher fuel costs from having to divert a bit farther is just not that significant of a factor here, and one that is easily compensated for by adjusting ticket prices.
Bumping the cost of an uncommon, already-expensive event by a few percentage points just doesn't move the needle much.
> And you cannot simply make a "sharp turn" at high speed. Your passengers (and the airframe on a large craft) are not prepared for 4G turns. They aren't even designed for 2G turns.
That's my point. Nobody is making sharp turns in airliners anyway. Routes are determined with weather accounted for in advance, and if a diversion around unplanned weather mid-flight is needed, airliners make long, sweeping turns to avoid it already.