What has already been done will have far reaching consequences. Each time this type of reaction happens, sports franchises will become increasingly averse to crossing borders. The financial costs and risks will be too high to bear, and I doubt insurance underwriters will want to get involved. This time it was South Africa. Next time the new variant might be here, Italy, USA, who knows?
Tourism will also take a hit, with sufficient people becoming increasingly averse to booking in advance such that airlines, airports, car hire, hotels will be tipped over the financial edge. They were already teetering, some already in administration.
IF, and it is IF, governments want the economic system we had to continue, they cannot perform these sudden lockdowns, indeed probably cannot do lockdowns at all. But, governments are about expediency, looking to the next election.