I don't think it's gone forever given the investments they put in it. I wouldn't be concerned unless we start seeing the Magic Happens parade floats appear in other Disney parks.
Ex. That drum thing that currently follows the cavalcades in
Disneyland was part of Happiness Is Here which ended in Japan in 2018. Some of the Happiness is Here floats were also used in Hong Kong's summer parade after some changes were made to them. Some of Disneyland Resort's Paint the Night Parade was sent to Hong Kong after its last run in California Adventure.
I'm guessing that Disney management thinks that having a night parade will lead to more people eating dinner in the parks while a daytime parade doesn't increase revenue in the same way. We have a CEO who is all about extracting money from guests while providing the minimum amount possible so I think we'll see Magic Happens return when the math works itself out that it somehow will lead to enough money in the short term to make it worthwhile.