Of course, a paid-only model would put a hard ceiling on the total addressable market, but they have an interesting challenge ahead in finding something that a sustainable number of users will want to pay for.
But, iOS only/first is a nonstarter for a huge portion of the population. If they're just trying to experiment is a small pond first to get it right (sort of as a throwaway version), then that is excellent. If they're planning to stay in the Apple walled garden exclusively or as a first-class/peasants model, then, well, good luck with that.
Wavelength is currently available only for iPhone, iPad, and Mac. An Android app is planned (see next item) … As mentioned above, Wavelength’s development team is very small. Two people, Henry and Patterson. That puts a limit on how much they can accomplish — hence the lack of an Android app at the moment.
Regardless, I don’t personally have any interest in this App at this time.
And it's especially true early in the development of any product, when major decisions are still being made, and even more true when there are sudden bursts of uptake, which can impact infrastructure in unexpected ways, which can then affect architectural decisions about the app.
Trying to do all of that on two platforms simultaneously is almost certainly an unnecessary dilution of effort this early in the development of the product.
That doesn't make Android an afterthought. It just makes it next.
In terms of addressable market, Android isn’t a stumbling block to begin with.