It's understandable because it's part of the muddled messaging of the movie. I posted about this earlier but Yoda's scene contributes to the "Destroy the past" narrative that some people took from it, even though Kylo is supposed to be in the wrong.
But I thought that was the message? I distinctly remember people feeling rather smug about how the film's message was meta and was poking fun at fans who couldn't enjoy the new movies because they were too much of a departure from the old ones or something.
I do agree that the movie couldn't make up its mind, though. Luke said the Jedi had to die, Ben wanted to wipe the slate clean of both Jedi and Sith, the bad guys technically weren't Sith even though they totally acted like Sith and then Yoda nukes what little Jedi manuscripts he could find, only for the books to have actually been saved and for Luke to say he wasn't the last Jedi after all.
Personally I would've enjoyed a new direction for the franchise where something new popped up besides Jedi and Sith. The new trilogy has thus far sorely lacked new ideas and that sort of thing would've been just the ticket.