alt Hacker NewsCitra (3DS) shut down with Yuzu. So not exactly. And Ryujinx did not take donations nor encourage piracy of TotK at launch, yet met a similar fate.
Regardless, for previous generations included, work on emulators and hacking consoles happened when the console was still current, of course.
You can’t start the reverse engineering work only after the console is superseded, by then it is too late for preservation, especially with live service games.
Citra shut down with Yuzu because they were owned by the same company that
It's true that Nintendo hasn't always sicced its lawyers on emulator developers for current gen - I'm fondly remembering the GBA era, when emulators based on leak dev kits started popping up before the console was even released - although that really only hurts matheusmoreira's point all the more; they're clearly OK with giving devs a fair amount of leeway. As for why that didn't apply to Ryujinx, it's hard to say, though my best guess is Nintendo was trying to get ahead of the "Yuzu alternative tears of the kingdom" Google searches.
This is a minor point, but I'll mention there really weren't any real NES or SNES emulators during their lifetime and yet they're among the most well-preserved consoles. Although sadly this did mean we lost quite a bit of Satellaview content, speaking of live services.