If you want to convince people to use your spaced repetition software over Anki, you need to tell us what's so wrong with Anki that can't be fixed with plugins and that's worth $10 per year.

You must demonstrate value above what Anki does.

I look at your list of projects in https://0xdev.gumroad.com/ and they're all pre-order of things that already exist elsewhere. To me, this smacks of "give me money, and I'll give you promises." Especially the project https://0xdev.gumroad.com/l/HelpFundMe?layout=profile

You want something for free? I'll give you something for free.

Anki absolutely can be improved. For new users, it's very confusing: having multiple decks, the separation between cards and notes, and the search interface are hard for new users.

Combine something that is simpler for new users with a demonstrably better algorithm and you might have a minimally viable product. But you need the product FIRST before you request money.

Give us something that we can run for one week and know that it's better than the free software that is Anki.