Last week, May 5's episode of Game of Thrones upset many fans when the patriarchy began to rear its head once more. When Season 7 first started, it felt like a sea change had occurred in Westeros. Cersei was Queen of the Andals, Sansa was the Lady of Winterfell, Yara was heading to the Iron Islands, women ran Dorne, and Daenerys was coming to collect all seven kingdoms. However, with the news of Jon's heritage now out, Varys announced he was ready to swing back to "c*cks." Daenerys sentencing Varys to death wasn't much comfort. In fact, it might have just proved him right. Warning: Spoilers for Game of Thrones Season 8 follow.
Daenerys knew that Varys would betray her from the beginning. She sensed it in him. After all, this was a man who had willingly changed alliances from Aerys to Robert to Tywin to Daenerys. In his words, none of those changes were about loyalty to the kings, but loyalty to "The Realm." It's a noble ideal to be sure, but also a convenient excuse.
Varys might have told Daenerys he would say things to her face rather than go behind her back, but that was out the window before Tyrion was done telling him Jon's real name. If only Varys had listened when Tyrion said: "Jon doesn't want it."
Varys did try, in last week's episode. Also, to be fair, Daenerys listened then. But Varys once again underestimated Cersei. She wasn't going to listen again. So, he did what anyone in his position would do. He tried again, with a new ruler who he believed would make a better king.
It was doomed to fail from the beginning. But perhaps moreso because Tyrion thought it would be a good idea to get a conscience, not at this moment, after all the plotting and taking behind her back last week. Tyrion is, in a lot of ways, a fool, but an honest one. He thought by telling Daenerys he would be doing the right thing. Instead, all he did was show the Mother of Dragons she was right from the beginning. Jon shouldn't tell Sansa. As far as she's concerned, Tyrion has betrayed her just as much as Varys. That would be the end of his time as her Hand.
At that point, it probably didn't matter anymore if Varys had said anything or not to Jon, though it was clear the moment he heard footsteps he knew the jig was up. He was arrested in his chambers and taken outside. That, if anything, answered how Varys would be sentenced: to die by dragonfire.
That is, after all, how Daenerys deals with traitors. With Tyrion on one side and Jon Snow on the other, she merely looked at Varys. Varys looked at Tyrion, saying, "Goodbye old friend."
Perhaps, Jon should not have been there. Of course she wanted him there, and of course, he had to be there to show unity. However, seeing how Daenerys kills with dragonfire may have done more to make Varys' point than any words he could have said on that beach.