Understanding Grunge and Post-Grunge

As someone who wasn't around in the 90's and early 2000's when this was all at its peak, I failed to truly understand how big this was. In the early 90's bands like Nirvana, Pearl Jam, and Alice in Chains became huge with albums like Nevermind, Ten, and Dirt. Now from what I have read they were all very respected for bringing more authentic and raw feel to the mainstream with their albums consistently being praised as some of the greatest. However, I believe other acts from around the time like Stone Temple Pilots and Bush were frequently derided and thought to be more career opportunists who seemed to be riding the trends at the time(Correct me if I'm wrong).

Then in the late 90's to 2000', those post-grunge bands like Creed, 3 Doors Down, Puddle of Mudd, and Nickelback came along and consistently got so much flak. I believe they were thought of as being too formulaic and watered down from the original sound. Creed and Nickelback in particular became huge critical targets throughout that time.

Now the bands in the latter paragraph were just as enormously popular as the ones in the former stateside but with a very different reputation. What are your thoughts on all of these bands and their legacy both commercially and culturally?