I think you’re absolutely right in this, but I do think the Spice Girls production is uniquely dreadful. I mean, there’s only 2 years between Wannabe and Sugababes’ Overload, and the latter sounds so much better it’s crazy.
Sound of the Underground was released only six years later than Wannabe but if you listen to them back to back they sound like they were written and recorded 50 years apart and on entirely different planets.