I'm a little confused by that article, to be honest. The Science paper they link seems to confirm that travel restrictions can have effect. Eg, from the abstrac

I'm a little confused by that article, to be honest. The Science paper they link seems to confirm that travel restrictions can have effect. Eg, from the abstract: " The travel quarantine of Wuhan delayed the overall epidemic progression by only 3 to 5 days in mainland China but had a more marked effect on the international scale, where case importations were reduced by nearly 80% until mid-February." My impression is that travel restrictions aren't a panacea, but can reduce or delay spread. (Whether or not they're appropriate with Omicron in particular seems to be a slightly different issue).