To build on KillerWhale’s point: Global aliasing can be achieved by adding this to the top of your note called a note.md:
---
aliases: an alias name
---
Which allows you to link to the note via either [[a note]] or [[an alias name|a note]]. Both will auto-fill as you type. (See help docs here).
Fanshu’s wording is ambiguous enough that I’m not sure if I fully understand, but here is my crack at it, as I also find this feature request appealing:
When an alias is defined under the aliases metadata, disallow creation of a file with that name and just have the raw link point to the file with the alias.
So, as per the example above, both [[a note]] and [[an alias name]] would point to a note.md with aliases frontmatter as defined above.
I also find this functionality desirable, because it is more DRY with regard to note-name usage.