They did nothing to support totk before the release date as even stated in this article from pcgamers

The emulation teams have forbidden all discussion of running Tears of the Kingdom from their Discord servers—Yuzu only allows vague discussion of the contents of the game, but requests for help or discussion of performance quickly earns chatters a deleted message and a warning or ban. To avoid being involved with pirated material, the emulator developers have vowed, at least publicly, not to release updates targeting issues with Tears of the Kingdom. “We are waiting for the game to release, so that members of our team can each legally dump their own copies of the game,”

The game only happened to run without any work by them (and it’s understandable after 6 years of development and the various documentation already available for the switch’s tegra chip) and this is happening every time a new game for the switch is released.