Why did Ed Greenwood and R.A. Salvatore dislike the Spellplague arc?

Question

The Forgotten Realms campaign setting includes an world-changing event called the Spellplague, which provided lore reasons for many of the mechanical changes introduced by Dungeons & Dragons 4e. For instance, the Spellplague caused wands with spell charges to stop working, matching how they were not available to player characters in that edition.

I have heard that Ed Greenwood (creator of Forgotten Realms) and R.A. Salvatore (author of many prominent Forgotten Realms books and creator of Drizzt Do'Urden) disliked this story development. What were their specific reasons for that?

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Answer 1

The main reason was described by R.A. Salvatore in interviews. He describes how the complete overhaul and moving the setting by 100 years would ruin his characters; a 100-year old human is no longer a good fighter. He even states that after the decision was announced in a private meeting between the FR authors and WotC, Ed Greenwood was completely devastated. They decided to immediately work on a plan to bring FR back to how it used to be.

You can watch a Sword & Laser interview here. The relevant part starts around 11:50. Quoting some parts:

Fourth edition, it was a shock. ... I am sitting there thinking, well, 140-year-old humans don't fight very well. ... I actually wrote a long letter to Wizards, ..., and said please don't do this. There are other ways to accomplish what you want. ...

When Ed Greenwood and I walked out of that meeting back in 2006, when we were told about the reboot for fourth edition, Ed looked at me and I thought he was going to start crying. I mean, these were his Realms, that had been taken away from him essentially by this big change. And he said to me what are we going to do? And I said, we are going to be smarter than them. We are going to think long term. ... We started planning back in 2006 how we were going to fix it for them.