The back of my envelope says that if a 50Wh laptop battery gave you 5 hours of run time, an average of 10W, then reducing that to 7W whilst keeping everything else the same would give you just over 7 hours. But it likely wont be quite that much in practice because all the components are constantly changing their power requirements and my envelope has a corner torn off at that point.
This seems to be primarily aimed at PCI-E 5.0 SSD adoption in laptops, where every bit of power saving counts.
2-3 watts is not bad considering (desktop) PCI-E 5.0 SSDs seem to consume about 5-10 watts.
Lower power consumption would also reduce heat, albeit I have no clue about the overall impact.
The back of my envelope says that if a 50Wh laptop battery gave you 5 hours of run time, an average of 10W, then reducing that to 7W whilst keeping everything else the same would give you just over 7 hours. But it likely wont be quite that much in practice because all the components are constantly changing their power requirements and my envelope has a corner torn off at that point.