The question isn't so much "can she grow and change" as "will the wider world let go of her mistake?" People as a group seem prone to not let things go if they get out of hand past a certain point (which this seems far past whatever that point might be).
Is it fair? Not really. Does that change the fact she's potentially damaged her ability to get another job like the one she was just let go from permanently? No it doesn't. Mistakes have consequences whether it is fair or not, and it will likely take a LOT of work to undo what one stupid tweet just did to her life.
You're right, but part of this is our tolerance towards others and how they screw up. And there are definitely unequal amounts of tolerance here directed at the various parties involved.
Some of that probably is due to the fact that the dude who got fired did make a public apology, and Adria didn't. But again, that's on her. That's not about what's ethical about the way we treat others. The way we behave as 3rd parties to all of this i don't think is contingent on whether or not Adria apologizes for something.
Is it fair? Not really. Does that change the fact she's potentially damaged her ability to get another job like the one she was just let go from permanently? No it doesn't. Mistakes have consequences whether it is fair or not, and it will likely take a LOT of work to undo what one stupid tweet just did to her life.