Close quarters travel has always been an infection distribution opportunity for bugs and cruise ship continue provide a perfect incubation crucible.
I suspect that it will be quite along time before cruising escapes Covid.
There has been a huge groundswell of folks wanting to return to cruising , some have had fun even with the risk management issues but many others have had great difficulty.
If the bug continues to degrade, ships and destinations may just let it rip, but it seems we are not there yet.
Press reports present a steady stream of disappointed travellers .. eg..
couple-stranded-spain-after-testing-positive-covid-cruise