Vittoria’s tyre range is as impenetrable as ever, but that Cycling Weekly test seems to compare the Corsa Speed tubeless tyre with the regular (non-Speed) Corsa tubular and tube-type clincher.
Since the Speed is significantly faster than the non-Speed Corsa among tubular and clincher models tested by Bicycle Rolling Resistance, the comparison doesn’t seem fair.
Additionally, the test used a 23 mm tubeless tyre while the others were 25 mm. With that power-monster riding in his aerodynamic position (both the opposite of what you’d want when testing rolling resistance, by the way, since those factors exaggerate aerodynamic noise), on a smooth surface, and using tyres of generally very low rolling resistance, a 23 mm tyre almost certainly gains more aerodynamically than it loses in rolling resistance compared to a 25 mm tyre. So using a 23 mm tyre gives tubeless a second unfair advantage here.
From what I’ve read and understood on this topic, tube-type tyres with a latex tube are still the fastest among similar tyres. The tubeless Corsa Speed is the only faster option than the fastest tube-type clinchers, but its problems of poor wet grip, short lifespan, and extreme fragility are now well documented. There is no similarly race-orientated tube-type clincher to compare to it, although the Continental Grand Prix Supersonic with latex tube is probably very nearly as fast.
The mass appeal of road tubeless remains surprising to me. There is a long list of disadvantages – many documented at length in this thread – and only one non-trivial advantage: greater resistance to small punctures. Since punctures are not a significant problem for me, even with lightweight tyres in glass-strewn Paris, this trade-off doesn’t work for me. The gouging price of everything tubeless-related is off-putting anyway.