Typically increasing the number of suns on solar cells increases their efficiency by a small amount, but the tradeoff is that the increased temperature decreases their efficiency - one terrestrial application of these sorts of cells is to sit at the centre of a field of heliostats in a kind of similar concentrating setup to solar thermal power plants, so you only need a small amount of high-efficiency solar cells operating at hundred/thousands of suns to harness a large amount of solar

These cells don't seem to be designed for that though

mrw somebody invents a material with a complex bandgap that breaks the shockley queisser limit