My post is in fact based directly on the Mastodon developer’s public statements to this effect
These apps are being developed specifically as means of onboarding new users to mastodon from the app store ecosystem’s “foot traffic”. It makes sense for them to want a limited pool of users for beta to ensure the apps are well polished before the intended audience of less technically inclined people unfamiliar with mastodon use them. How you obtain the pool of beta testers is probably not overly important, using an invite system for example would probably result in largely the same group of insiders who are likely to be patreon supporters having access anyway.
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