I’m pretty sure that Mercy’s GA was 30m, not 20m. Also, Mercy’s GA at the start of the rework had a speed boost along with it’s range. Such a speed boost was removed. So no, Mercy’s GA was certainly changed, and is now slower than what she had at the beginning of the rework.
The issue is impact. With the exception of maybe, damage boost, nearly all of the buffs in her abilities she had in Valkyrie have been either removed, or toned down in place of slightly increased range. Her healing was reverted back to the healing she had in 1.0 and her self regen and speed have also been nerfed. She no longer can instant rez during valk, and now she can only rez once on a fixed 30 second cooldown, with her being locked behind a cast time.
For me at this point, it’s better off if they start from scratch, back to where she had true fair and fun balance. It’s time for them to revert her Ultimate back to mass rez, not what feels like a glorified spectator cam. My opinion.
Oh here we go. “Time for the generalizations and insults because my opinion on Mercy differs from yours…” Go on and get your projections out of your system then…
You seem to have not been aquainted with one of the most popular threads in this forum, allow me to inform you on Why I Have Yet to Not Despise Mercy’s Current State. Me and literally 1000+ others can agree that this details exactly why she is unfun. Here, educate yourself. 
I’m sorry, where have I said that “I only like Mercy when she was OP?” I literally said that not everyone is happy with how she turned out and they have a right to have a say about it. How did that translate in your mind as “Oh they mean they want her OP?” [citation needed]
I’m here saying that everyone’s opinions matter on their frustrations with mercy and while I have a view on what I think she needs, that one opinion isn’t better than the other in what should be done with her. What are you trying to say right now?
~Sincerely Yours xoxo,
a Lover of True, Fair, and Fun Balance.
xavvypls 