Square Enix doesn't have the talent or skill to adapt it properly. It's too much for them or Hollywood to adapt without butchering it.
Well as far as I know the Malazan books were based on the author and his buddy's D&D campaign and they did start to get pretty ridiculous around the 5th book in a way that would probably fit well with a jrpg. I couldn't finish the series. It got so dumb it was like reading about a bunch of superheroes. It's another series on the pile that made me give up on those long ass fantasy series in general. That was the worst trend to ever happen to fantasy books. Endless series of 1000 page books with a glossary the size of a normal book at the end. I blame Tor. They just kept pumping them out for years and years.
Not D&D. It was a GURPS campaign setting that they picked up and turned into a failed movie script pitch. Erikson expanded that into the novel Gardens of the Moon, and eventually ran with more of it for 5 novels before Esslemont started getting his own series in the same shared universe published.
Between the two of them, they have created dozens of works. 2 complete main novel series, prequel trilogies and sequel trilogies with stylistic changes to the writing, and comedic novellas focused on the travelling necromancer side characters everybody liked. Everything spanning thousands of years of history.
Outside of Middle Earth, the series is untouchable for mature high fantasy world building. Both authors are archeologists, and aren't actually stupid when it comes to slowly approaching narratives and characters, their motivations, what they show or tell you from their perspective, whether true or not.
It's the most dense, master class fantasy work since LOTR and there is still more coming. That is down to Erikson material more than Esslemont, but he's above average in his own right.
The most damning thing about the series is how dense and inaccesible it is. Up front, you have no handholding. You take the ride. You don't begin to understand what's actually going on or how the world works until you have read multiple books that span multiple narratives with different characters on different continents.
A Song of Ice and Fire was an easy to read fantasy behemoth as it came along, like Memory, Sorrow, and Thorn before it, but it was never finished and probably never will be thanks to HBO money and old man GRRM being distracted by wealth, food products, his own nihilist inability to write heroic endings. A Game of Thrones and 2 sequels were good, ending at a breaking point for a time skip that never happened. The rest so far is a roll of toilet paper by comparison.
Malazan is already done, meandering in the fringe spinoff extra stuff, and in a hundred years people will look back at the whole thing for what it is. Something Tolkien would likely have been impressed by.