I recently started TNG and saw that episode for the first time a week or two ago. When she died, I literally did not believe it right up until the end of the episode because of how anti-climactic her death was. I was absolutely sure it was going to be a fake-out.
When the episode ended, I had to look up why she was written out because I was so utterly perplexed.
... And it turned out Tasha really died, though the article did mention the actress returning on a few occasions. It sounded like the first season was a little rough behind the scenes, and the actress was also worried that the role would be too repetitive(?)
Ultimately, I feel kind of bad for the actress since TNG is widely revered as one of the best sci-fi series and she missed an opportunity to be a major part of it; but I can understand why she felt the need to leave. Plus this change gave Worf more time to shine, and also made room to introduce Guinan; so I really can't be mad.
I also still find it pretty touching when the cast references Tasha and mourn her (like Data's hologram in the episode where they legally have to prove his sentience).
I just kinda like to dunk on her after I heard she wanted a permanent out from Star Trek. Damn it, I'd love that shit, just as random aliens in the background or whatever. Acting like being known for Trek is not good enough for you... pffft.
Remember that at that time Star Trek was in really rough shape. Most of the cast thought TNG was a joke and would get cancelled after 1 season. A bunch of the scripts were leftovers from the 60s that they reworked slightly, so overall the quality of S1 was bad and the cast were also reacting to that.