You have to look to the way the voting works to understand why that might be the case. It may also explain why the two listed UK restaurants are there, when they’d probably not hit anyone Top 50 UK restaurants, let alone Top 50 World. Of the five in the Top 100, all are in London and three are in the same small district of Shoreditch.
Treat it as a bit of fun, designed to feature this year’s internationally “trending” restaurants, rather than an assessment of quality.