Kind of a history lesson:
Nighttime at DAK is something that Disney has wanted to do from the get go. Towards the beginning of the park’s life, it had some later hours, and had nighttime safari’s, but the park’s offerings were at the time overwhelmingly daylight dependent, so the demand at night just wasn’t there. Like most waterparks, the demand set the hours to have the park close around 5 or 6 every day. As time went on, the ability for the safari to run at night was disabled, but new offerings pushed the hours a little later into to 7 or 8 during peak seasons.
Shortly after Everest opened, there was an initial push to get the park ready for nighttime primetime. The plan was to anchor the nighttime offerings with an on-land night parade (which at one point was called Rivers of Light) made to be inspired by a lantern festival (sounds familiar), but for some reason I think the original night parade was going to feature characters (in the Jammin' Jungle Parade sense, not the Festival of Fantasy way).
A recession and couple of delays later, Disney announces the Avatar expansion, and with it came the almost prerequisite that the park would have to be open at night, considering nighttime is when some of the most iconic visuals from the franchise take place. So, plans were decisively put into motion that Animal Kingdom had to be ready for nighttime operations in time for the land's opening. They were tentatively set to beat the land by a year to get the park used to nighttime operations (and increased crowds due to the expected draw of AVATAR), which led the park to embark on it's own version of project Stardust.
The first thing to address was crowd flow in the park. While the park's lush environment was great, the combination of planters and entertainment offerings like the Jammin' Jungle Parade were murder on the park's crowd flow. With the soon to be increased volume in crowds (and the slight influence of costs) they decided to retire Jammin' Jungle parade, and retire the park's parade route. No parade route meant that the anchor nighttime entertainment couldn't be a parade on land, so after a brief look to the Tree of Life (whose viewing area was way too small) the plan to make an amphitheater on the Discovery River area was put into motion, and after a few proposals, Rivers of Light was selected. Of note is that it was made to feature multiple performers, some of the largest water screens ever made, and fully autonomous barges with no driver on board and no track of any sort (an industry first). We'll come back to this.
In addition to this, the entire park wasn't 100% made for nighttime, so a lot of money went into smaller enhancements, a nighttime lighting package for the park, projection mapping on the Tree of Life, and changes to many rides nighttime lighting packages, but the was still one issue. Safaris couldn’t run at night anymore without offering a significantly inferior experience, so a lot of effort was put in to get the park's premier attraction able to run at all hours of the day. To be ready in advance of Avatar's Summer 2017 rollout, the nighttime offerings were all meant to be one cohesive rollout in Summer 2016, but then problems started arising with the nighttime's star anchor: Rivers of Light.
After already having multiple elements cut (like more dancers and live musicians), Rivers of Light was still having issues with it's driverless and autonomous tech. Multiple smaller elements (Like the small lanterns on the water) had trouble working synchronously. Multiple collisions occurred, and a few of the smaller lanterns ended up at the bottom of the discovery river. All of a sudden, the show lost one of the best lighting elements. And the big floats still couldn't cooperate. Meanwhile, early impressions had the show pegged as a "too long and boring" without some of its main elements. After months of technical issues, the decision was made in the Spring of 2016 to postpone the debut of that show until its techinal issues are resolved. This gave them a nighttime rollout without its star anchor, which left them to scramble to use their limited resources (an amphitheater, water screens, and a bunch of lighting rigs) to throw together a nighttime spectacular in a matter of weeks. All things considered, it is impressive as to how good JB:AwM turned out all things considered, but it still bombed due to the water screen technology (a combination of dark imagery on a screen that already had some issues did not end well) and awkward pacing. This show tanking led the entire rollout to be bungled (ToL Awakenings was viewed well, but parts of the park were still too dark and Safaris was still viewed as inferior to the day version), and ultimately had them pulling back on the hours once the summer promotion had ended.
Then, after moths of testing and show adjustments, Rivers of Light arrived. Unfortunately, so many elements had either proved to be weak (the water screens) or cut (the smaller lanterns, and parts of the show like the initial processional) that the final result was lackluster. It had a great backbone, from music to visuals to technology, but it just didn't resonate the way they expected it to. The final blow occurred when Avatar's nighttime effects also underwhelmed. The area appeared too dark and they simply didn't capture some of the night effects from the movies. This was effectively the death knell, as Animal Kingdom didn't have a "prime time" nighttime anchor. While the supporting lineup was solid, AK's stars (Pandora at Night and RoL) both flopped. Since then, some half-butted measures were made to try to remedy the situation like putting the Shaman's back in the audience, slightly retooling RoL, and even some changes to Pandora's nighttime lighting effects. During all of this, nighttime safaris continuously had lower GSATs, and eventually the only thing "in the green" at night was the ToL Awakenings, which is why they got added to the back of the tree.
A while before the pandemic, nighttime safaris became the latest budget cut, and RoL: We Are Done had reduced, if not eliminated showtimes. Now, the new COVID schedule mandated a park take the "early" poop, and with its after dark offerings effectively dead, AK became the victim. With that DAK at night is currently dead, but it could just as easily be revived. As soon as Disney decides on a new Nighttime Spectacular and is willing to spend on it, it's just a matter of turning some other things "on."