44 applications doesn't seem like a lot for a new program, and presumably not all of them will be approved. By comparison, the $5M USD "Trump visa" has had 68,000 applications since the program went live June 12th, and that's to live in a country sliding into fascism.
My guess is that the numbers are so low because $5M or $10M (NZD) is a pretty heavy lift, and the people with that kind of coin lying around have business interests elsewhere that makes residing in the remote locale of NZ not very attractive. Yes, I recognize that they would only have to spend 21 days there over three years for residency, but why would you even bother unless you wanted to actually live there? There are lots of other desirable places in the world with relatively easy residency requirements that are closer to the business centers of the world, and you don't have to fork out several million dollars.
I assume that the goal is to bring in wealthy, educated people who will make capital investments and ultimately help grow the economy. I think a better strategy than requiring such a big investment would be to make the investment number significantly smaller (say $1M NZD), and then give credits to potentially reduce that to some extent for people with education or skills that are sought. Right now, the Trump administration's decimation of science research funding has a lot of PHDs looking to jump ship, and New Zealand could probably pick up some smart people with the right program.