Tbh like if we are to discuss this properly, I think achievements by generations is fine
Because like 2nd 3rd 4th gen are quite different.
If a 2nd gen group for example achieve 500k sales, this might seem like such a small number compared to the huge sales of 3rd/4th, but for 2nd Gen this is huge.
2nd Gen thrive on digitals groups like there are way many more BGs charting back then.
3rd Gen (could be wrong) thrive on concerts, bit of digitals, bit of physical sales.
4th Gen it's all about the sales, bit of concerts now that covid is not as prevalent (covid put a huge halt to this), and digitals are kinda only relavant for GGs
The generations are somewhat different which is why I'm still OK with people quoting achievements based on generations.
And this is also a huge reason why I think all the 5th gen nonsense is pure bullshit, because there is literally nothing separating the newly debuted groups from 4th gen except for the fact that you want to mediaplay your newly debuted 2023 groups as the first or highest achieving group of your made up generation