Star Wars tie-ins are reinforcing the strange parallels between Palpatine and Yoda. For millennia the Sith operated in the shadows, waiting for the right moment to have their revenge. Palpatine was the culmination of all their plans; the Sith went into politics to beat the Jedi, knowing their enemies were politically naïve and disinterested. Palpatine maneuvered himself into becoming Chancellor of the Republic, and for over a decade he worked side by side with the Jedi, holding countless meetings with members of the Jedi Council - including Master Yoda.
Yoda was undoubtedly the greatest threat to the Sith. The aged Jedi Grand Master had centuries of experience, and he had cultivated a tremendous degree of sensitivity to the Force. There is a sense in which Yoda had become the very definition of the Jedi, both to the galaxy at large and to the Jedi themselves; his long life and his love of Younglings meant his philosophy of the Force had become dominant among the Order. Recognizing this, Palpatine seems to have made Yoda his particular focus, choosing the Grand Master's former student Count Dooku as his Sith Apprentice. When Palpatine finally emerged from the shadows in Star Wars: Episode III - Revenge of the Sith, he and Yoda engaged in a phenomenal duel - one Darth Sidious clearly took great pleasure in.
Curiously, though, there are striking parallels between Palpatine and Yoda. The comparison was recently highlighted in Star Wars: Crimson Reign #3, which revealed how Yoda hid himself on Dagobah during the Dark Times; he took advantage of the fact Dagobah is a powerful light side vergence in the Force, one that could conceal even his luminous being. The technique is an inversion of Palpatine's own, for there have been hints Darth Sidious took advantage of the darkness of an ancient Sith shrine buried beneath the Jedi Temple on Coruscant to conceal himself on the ecumenopolis.
This revelation only reinforces the curious narrative symmetry between Palpatine and Yoda; what one was to the Sith, the other was to the Jedi. Palpatine concealed himself from the Jedi, and through his plans the Sith ascended to power and overthrew them. But Yoda hid himself from the Sith, and because he mentored Luke Skywalker, the Jedi ultimately overthrew the Sith once again. There is, of course, a crucial difference: Palpatine's plans were focused on his own ascension, but Yoda understood he had to pass the torch on to someone else. In the end, Luke didn't defeat the Sith because he acted in accordance with Yoda's plan, as the Grand Master didn't believe Darth Vader could be redeemed, and simply thought Luke would be the one to kill the two Sith. Instead, Luke acted completely outside Yoda's philosophy of the Force, and his act of redemptive love was what truly thwarted Palpatine's plans.
Tie-ins have created yet more parallels between Yoda and Palpatine. Star Wars: The High Republic has implied Yoda's dominance among the Jedi was far from benign, because his philosophy of the Force actually became restrictive upon the Jedi, leading to their decline and encouraging the imbalance in the Force that would require the Chosen One to correct it. In contrast, Palpatine was more a Sith heretic than he was a committed Sith, for he cared little for the Rule of Two, instead focusing on what could be called the "Rule of One" - a perspective that meant when he finally died for good in Star Wars: The Rise of Skywalker, he left no successor, and the line of the Sith was destroyed.
Both Yoda and Palpatine were, in their own ways, responsible for the downfall of their respective Orders - a fascinating twist in the Star Wars saga.