Oh really? SponsorBlock is without a doubt one of the more popular OSS applications out there, yet the Patreon of its creator barely breaks the 200$ mark[0], which isn't even enough to sustain server costs for just the WebExtension version (source: same Patreon linked before). People just don't donate to FOSS, corporations do[1] and no corporation wants to fund something like SponsorBlock since it's existence is arguably anti-corporate (I'm not the ideologue for that spiel though, sorry to burst that bubble).

The 100$ yearly publishing fee just straight up is a wall that prevents the OSS iOS ecosystem from thriving. It's just high enough that it's hard to justify putting an App out there unless you want to make a profit from it.

[0]: https://patreon.com/ajayyy

[1]: Or rather, most have been shamed into doing it and only pay the bigger projects. Anything smaller just falls to the wayside.