It's all about giving people more headroom. Some people will use that headroom to drop temps, or fan RPMs, and others will use that headroom to overclock, and get an extra couple % in performance.
Having the choice to do either one is not a bad thing.
@Dawelio is right that in practical terms it doesn't mean too much, as dropping temps from 70-50º isn't a meaningful difference, except in edge cases,
if you are running at stock clocks. But that extra headroom (280's are a significant amount of area over 240's)
can be used for many things --- water blocked 3090 + 16 Core Ryzen with a nice OC on both, for example, or the same, but with fan RPM's turned down to the 750 range, and lower pump speeds for an even quieter system.
In either case, with the sharp rise in TDP we've seen with the latest generation of GPU's, I think the headroom will be welcome by many who like to not ride the thermal edge of their chips, or those who enjoy overclocking, and want to do a shunt-mod on their 3080 or 3090.
As for what you choose to do with that space, that's entirely up to you as the person choosing to build a system in this thing.