Updating incident details via email

I'm looking to extend  's topic from a couple years ago:  RE: Email Commands to update ticket status / assignee etc 

Is there any other way to manipulate a ticket's details via email or write automation rules that are more dynamic?

Over a decade ago now (man, I'm getting old...) I used another product where you could do that with special text in your email body: https://docs.bmc.com/xwiki/bin/view/More-Products/Footprints/FootPrints/fp2021/Using/Using-FootPrints-with-a-Customer-role/Editing-your-tickets-via-email/ almost exactly the way Afroon described it. 

As far as I can tell, you can't do *all* that with automation rules since all of your actions have to be predefined statically. 

Example: a tech asked "can we make it so that if I email in a ticket, it gets assigned to me?"

short answer is yes: if requester is bob then update incident, assignee=bob 

However, can I do that at scale??? not that I'm aware of. If I have 40 technicians, I'd need 40 rules: one for each. My other thought was having a magic keyword like -selfassign- or something and then the action would be update incident > Assignee = Requester. However, it doesn't look like you can use variables like {{requester}} and there aren't options like Incident Requester. 

Before I go submitting this as a feature request, is there something I'm missing? Is this totally doable and I'm missing it?

Thanks in advance for your time