I haven't been able to receive email updates on discussions, for years...and I'm good with it; wouldn't go back if I could.
Given the buggy nature of the site lately, I wouldn't worry about it. Just click on updated discussions, (in the upper right), and go with it. One stop shopping.
__________________
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Ben Franklin
__________________
"Did you get my e-mail?" - "The biggest problem in communication is the illusion that it has taken place" - George Bernard Shaw, 1856