Again, please go back and read my previous posts.  The evidence that Daenerys is losing control is very slim.  One line does not make her evil.  Again I'll go down the line of things she's done this season that point to her being in control of her faculties:

1. Pardons Jaime
2. Tries to play nice with Sansa
3. Agrees to a siege/blockade plan as their primary strategy
4. Breaks off from her suicide charge at Euron and is forced to do nothing as her ships are attacked
5. Literally begs Jon not to tell Sansa about them because she knew what would happen
6. The first thing she does with Jon when they're alone for the first time since the revelation is ask if they can continue their relationship
7. Realizes that Tyrion's blind spot for Cersei remains, but humors him
8. Rewards the son of Robert
9. King's Landing is still standing when Jon arrives a fortnight later
10. Is fairly tactful and restrained in her dealings with the northerners who distrust her despite being used to being practically worshiped.

You have one line where she basically says she's going to destroy a tyrant one way or another.  I have a long list of Daenerys acting like the exact opposite of a madwoman on the verge of becoming the next Cersei.

Maybe I'm wrong and she'll be super evil next episode.  But if she is, then that's REALLY bad writing because the only setup for it isn't Dany's actions, but Varys's musings.  And if there's one thing that should be easy to write, it's a character that's starting to lose control of her temper.

Damn, now I understand how Euron can look so smug all the time. Those ships of his are so powerful they would rival 18th century ship-of-the-lines. I mean, not only do they have teleportation and stealth technology but are also equipped with some high-tech long range rapid fire ballistas that do more damage than cannonballs. Must have had some of those "fuck you physics"-runes applied to them. Of course, it also helped that Dany's ships were made of cardboard.

But seriously, how the heck did Dany not spot that fleet? She's travelling to Dragonstone, which is pretty darn close to King's Landing so you'd think she would be at least somewhat cautious.

And then there's Bronn also doing some of that teleportation, Jon giving Ghost the middle-finger (why!?), etc. Sigh. How did we go from the brilliance of the first seasons to...whatever this is? What happened!?

Edit:

And what the heck happened with Bran and the Three-eyed raven and all that? Was the entire point of his adventure to learn about Jon's real name? Because outside of some creepy staring and muttering that's the only thing he has accomplished since his return.

Everything you've explained is literally a single quote that was hardly dispositive.  Meanwhile, the whole of her character's behavior in recent episodes point in another direction.

That's not complex changes.  If that's where they're going, they did a terrible job.

And, no, it's not because I love Daenerys.  I'm simply watching the show, seeing the inconsistency in this theory that Daenerys is out of control when matched with her state of mind throughout the season.  I'm noticing that they half-quoted Varys's loyalty oath where he swore not to go behind her back like he did the other kings.  I'm noting Jorah's last bit of advise to Dany was to trust Tyrion after his recent failures, who wants to believe in his queen.  This feels like the final storyline for Varys and Tyrion, not for Daenerys.

Could I be wrong?  Sure.  It's very possible the writers are simply booting this storyline.

Well you must not have been paying attention to the last episode, because they made it pretty clear she's lost all objectivity on being good or evil. Her view now is that whatever it takes to get on the Iron Throne is justified, as it's her right:

"Do you believe we're here for a reason, Lord Varys? I'm here to free the world from tyrants. That is my destiny, and I will serve it no matter the cost." -Daenerys

"I served tyrants most of my life. They all talk about destiny." -Varys


And who said they'd be giving her an easy way out? She may avoid having to massacre thousands of innocents, but the sooner she gets to the throne the sooner she just becomes the next despot/Cersei, paranoid someone better suited (Jon) for the role is about to take it from her, as they've already shown the beginnings of.

You ever stop to think that it might be because Varys is the friend who saved his life and the closest person to whom he can relate to best in the world and Daenerys is his queen and he's being forced to choose between them?  If you actually watch the scene, Tyrion knows that beyond Varys's dressing his intentions up as nobility, they're discussing regicide.  Tyrion then asks Varys not to do it.  There's actually a moment of fear their within Varys.  He realizes at that point that he's committed himself to deposing Dany and Tyrion is not on board.

Seriously, are you going to expand your point out beyond that one line and pretend that they've developed more than that?  Yes, I know they tossed out the possibility.  There's a whole conversation between Tyrion and Varys about it.  There was nothing subtle about the notion.

What I'm saying is that it doesn't match the way they've characterized her this season.  That tells me that either they're incompetent and wrote her wrong, or there's a swerve coming similar to how they feinted the conflict between Arya and Sansa last season to ensnare Littlefinger.