You mean writer, I know there are writers for the show, but they are following the original books for the first few seasons. Making Daenarys likable was not something the writers of the show came up with, Daenarys was always likable in the books too. I know the last 2 books are not out yet, but its clear GRRM was planting these seeds all along if you pay attention. She has always been a likable sociopath, but previously all of her interactions had warranted the outcome, so not many including me noticed it, until she burned King's landing w/ everyone in it.
they followed the books, but they did cherrypick what made it into the show and what didn't.
and how certain actions were framed or weren't. and for danny, they framed everything in her favor right until the end. even early season breakdowns and fears of not being accepted if jons secret came out weren't exactly the insane paranoid delusions of a going crazy woman.
and killing a dude plotting her end isn't exactly far from the norm in westeros.
overall, her big break felt more like she was possessed by a spirit at some point, instead of developing her character.
nothing she did this season really overlaps with what she did in seasons past either, besides killing. before, there was a greater good, always. she didn't kill innocents, she killed the puppetmasters at the top. she didn't kill just simply because it was the most convenient for her, though many of her kills helped her personally too.
of course she always killed, like most every other character in this show. but she killed what were objectively bad people or enemy soldiers, not randos that didn't exactly care who ruled them either way. until 2 eps ago when she killed just people in a city for no reason, after winning.
there was no build-up, no shift from killing the lords and ladies in (often abusive) power and their armies to killing most living beings just in her physical way. she just snapped for very thin reasons.