Substack articles not indexing well?

I have been posting some articles to large web2.0 sites recently and have found some to index and rank really quickly (Medium for example) and others not faring so well at all, such as substack.

I thought that substack would be a bit more prestigious than medium but crikey is there a difference. I have middle of teh road review content ranking in the top 3, easily, with Medium yet have only managed to get 1 out of 3 (arguably) higher content indexed on substack and no ranks whatsoever.

Has anyone else noticed this? Am I late to the party? What web2.0 / parasites are good for ranking content these days?

Substack is more of a newsletter platform than a blogging platform. You'll rarely ever see substack articles in SERPs for that reason only.

Substack is terrible at SEO almost by design. It creates a closed ecosystem where the traffic is generated by and stays on the ecosystem.

It's fairly useless for building an audience, it's basically free hosting for those with an audience.