Can't they put an Army General in charge of West Coast Ports?

Because military logistics is different than civilian logistics. Military "triage" for supplies is different than civilian triage. It would take the General AT LEAST 3 months to fully understand the situation and adapt to civilian rules, regs, and priorities. 3 months in which the situation is likely to get worse, not better. After that, sure, we would likely see slow and steady improvement. And in 2 years, everything would be running smooth and pretty. But is it worth the 3 month cluster for the 2 year payoff? Especially as the civilian authorities can likely get us there in 2 years (or quicker) anyway?

But none of that is NEARLY as relevant as the fact that a General simply doesn't have the authority necessary, unless we invoke martial law. And I don't think any serious people believe this warrants martial law.

Unless POTUS declares a National Emergency- won't happen, unions will shut down everywhere. The service has handled such in the past- coal mines, steel mills, railroads, but it left a damn bitter taste in an awful number of folks for years.

Logistics is a complicated issue. For the West Coast ports delays, it is not just one problem that we solve and life returns to normal. Multiple factors include aging infrastructure, different governments involved (federal vs. state vs. local), lack of workers and ongoing COVID pandemic just to name a few.