Well, this concept is dead in the water, isn't it? I wonder what on earth happened? Especially after such a grand announcement. Feels like a decade ago that this was going to happen.
In terms of what happened to Eurovision Asia, it looks like two things happened.
The first is that Eurovision Asia was announced prematurely, before enough planning and preliminary talks had been done to see how achievable the project truly was. This may have been because Australia's one-off appearance may have been intended to be more permanent by Jon Ola Sand, but that doesn't mean that Australia knew that, or that enough of the EBU felt that way. It is important to note the timing. Australia made a 'one-off' appearance in Eurovision 2015. In March 2016 the idea of Eurovision Asia was announced. It is possible the timing of the Eurovision Asia announcement was part of helping to convince the EBU of Australia's worth in remaining in Eurovision as a bridge between Europe and Asia.
Or it could have been out of eagerness and optimism.
The second thing that happened, as has been publicly stated, is that Eurovision Asia proved to be too
geopolitically difficult.
In February 2020, TVTonight (a major source for reporting developments in Australian TV)
stated that their sources had said that one of the key difficulties was that several broadcasters were reluctant to participate if China was not involved. That may be related to geopolitical reasons. Other geopolitical reasons may include any relevant lingering barriers between South Korea and Japan r, which arose out of past conflict. Those barriers opened up in the 2000s but not fully.
That same update saw this statement from Paul Clarke:
"We were in Japan in December but ultimately it doesn’t come down to just SBS being interested. It has to be some major partners as well… and Northern Asian partners. It’s just still in development." The reference to Northern Asian partners means that China, Japan and South Korea are important to whether or not Eurovision Asia happens in future. It seems that interest in Japan is solid (as evidenced by that December 2019 meeting) but that isn't enough.
A possible part of the issue is that getting suitable partners on board may be complicated by Eurovision Asia being part of the Eurovision brand and as a result, certain arrangements that might get more nations on board may not be acceptable to the EBU. For example, allowing individual broadcasters to not be bound to broadcast the entire show.