I agree with all the client responses already shared in this thread! I thought for sure I was missing something or just did not have something turned on... but to eliminate the auto-correct feature and replace it with this Editor feature is absolutely absurd. This is going in reverse in regard to productivity and efficiency. Editor must be opened in EVERY SINGLE email, nothing automatic about it, AND it does not even correct capitalization at the beginning of your sentences, and I have the capitalization feature checked.
I am very disappointed with this "downgrade", and I am going back to the old Outlook right now. I really hope Microsoft makes this error a priority to be corrected before the "official, permanent" change is released.
On a positive note: I love the option given to remove the "top results" from the search feature.