That sounds like a good feature - I think the app is trying to replace current jira etc functionality for now, is that something that Jira and other offer?
Jira has a self hosted version at very reasonable price ($10 one time for small teams with a single server up to $500k per year for high availability setups with >50k users).
The same is true for all other Atlassian products.
The next tier is 25 users for $2500. So it went from $1 per user to $100 per user.
JIRA is, by its nature, a multi-user software. The $10 for 10 users is clearly engineered to get small teams to commit to using it and then squeeze them when they grow.
That is a reasonable strategy for what is a product for companies i.e. enterprise software.
It wouldn't work for a product that is primarily for people who are paying from their own pocket, like, I assume, everyone here that expressed the want for a self-hosted version.
In a personal use case you more than likely stay below 10 users forever. If you are a company paying multiple employees 2500 should be easy to justify: that's 25 users at 10$/month for Jira Cloud would cost you 2500 in 10 months, with hosted Jira it's just a one time payment
Notion is a hierarchical note-taker/wiki with some additional features like simple databases, task lists etc.
They are not the same kind of software.
Also, you can link notion pages. They have a block element that is a link to another page and for inline links you can use the regular link (each notion page has its unique, stable url).
Notion does but it's not well implemented. If you copy a link to a notion document and paste it in another it does create a link. Wish they made it a little more well defined though (I don't want to copy a link and paste it).