The objective sound simple to me, but it seems in Jira it is not:
Objective:
Allow only specific types of links between elements.
Why:
The list of possible link types is way way to big for a regular user to oversee and choose the correct one. In order to have consistency it is therefor mandatory to limit the possible choices.
As far as I have found out so far, it is NOT possible to limit the selection with Jira on board tools. Not for the whole instance nor for a single project. Correct me if I'm wrong
Thus I tried to make a step further to at least clean up and inform the user if he has done something "wrong".
But there comes the next few quirk/inconsistency (IMHO):
I tried to create a automation which is triggered when a new link is created. As for the user, the list of possibilities is endless. So I tried to grab ALL of the types which should not be used: (why not c&p from clipboard in this editor here? -> inconsistency)

Now comes the first quirk: It's seems NOT possible to refer to the just created link itself, the one which triggered the rule - which is the one I want to simply delete. Am I wrong?
It seems only possible to delete ALL links of a specific type - In my case that could be accepted, but what would you do if you want to just delete this specific created one?
Ok, so let's delete all of a specific type. But there comes the next quirk: The selection list looks very different.

And, only for now, comes the last quirk: While in the trigger you can select "Requirement" there is no such possibility to select "is required" or "required by" or similar. What am I missing?
Question:
1. Can I somehow limit the link types without an additional app/add on
2. Why is the selection different?
3. Is there a way to really delete only the link triggering the rule?
4. If 3) is not, how to achieve consistency between "when" and "then"
5. What/how to select for "requirement"