In tinymash, there's a concept I refer to as author space or author spacing.
So there's the website, or "the root", and there's author space.
An author space is associated with a user, the root space is not. All admin users can control the root space, whereas an author can only control the author's own space.
Authors can choose to expose their content to the root space, which is primarily of interest to a blog like website. This allows for "aggregation" of content to the root space. Authors can also control a few rendering / display settings for their own space.
As a side-effect, this also allows you to host multiple blogs or sites under their own /sub-url You can create authors that are used as designators for a given section of your site. You then lock the user so that logins with those usernames are disabled. As an admin, you can still build content for that author space.
So, these can all be their own spaces:
https://domain.com/gardeninghttps://domain.com/techbloghttps://domain.com/music
This does not require any special setup other than what was mentioned above.