Remathilis
Legend
Isn't it more than a bit of a fallacy to call the side you don't agree with "radical?"
Also, if I'm not mistaken, 4e didn't fail because it was trying to make the game more open, right? It was the planar cosmology changing yet again, multiple gods being replaced by a magical disaster, the game becoming more like a video game, books that people didn't seem to want to buy, and a lot of other factors, right?
I don't think WotC will make a 4e mistake again, and this certainly is not remaking 4e.
Well, two things.
Obviously, the term radical can mean different things. Changing the d20 to a d100 for task resolution would be radical, but similarly a dozen small changes can add up to a radical change as well.
Fourth, for example, did a small change called "assign each class a role" (defender, controller, leader, striker) that kindasorta mimicked the classic positions classes have played in D&D and were codified in countless MMOs. That alone shouldn't have been controversial. However, all classes were made to fit into those boxes, often limiting their use in other roles that 3e (and later 5e) could be built for. A fighter HAD to be a defender, his tools were built for taking hits and limiting foes. A bard HAD to be a leader; her tools were built around healing and buffing. Etc. Further, classes that could previously be other roles (like a druid leader or a fighter striker) were initially limited, weak, or required later splat-books and extremely specific builds or subclasses to work. So a small change (lets assign each class a role) lead to HUGE change in class design and identity.
Now, let's take a proposed example: remove evil alignments from all humanoids. Again, it makes sense in context; humanoids should be allowed to choose an alignment (if such a rule even continues to exist). However, that creates the snowball to worldbuilding; where do the good orcs live? where do the evil elves live? If orcs can be equally good or evil, why not ogres? If orcs and goblins are no eviler than elves and dwarves, should the latter be in the PHB (and the latter the MM)? Should campaign guides and module assume more halfling bandits and orc innkeepers? Should every setting (including far darker ones like Greyhawk and Ravenloft) assume multi-species societies living in close proximity? The ramifications of such a change are far more than just removing "Chaotic Evil" off the orc statblock.
Which is why I worry about too many changes coming at once. For the last month, discussions about problematic areas of D&D (such as race, alignment, cultural appropriation, and lesser ones of stereotyping, ableism, misogyny, etc.) have been filling up messageboards and social media. The drumbeat is getting louder. Now, maybe things die down again eventually, but I can't shake the feeling that WotC will need to do more and more to "modernize" D&D, and the issues are going to be much more central to the game than promoting gender-fluid elven deities or removing some adjectives from the Monster Manual. I worry that WotC will make a dozen small changes that lead to a big change in the game, much like how 4e made dozens of "fixes" to outdated concepts and confusing lore that was soundly rejected.
Put another way, the road to Baator is paved in Good Intention.