Where exactly is the boundary between Drimnagh and Crumlin? And indeed, Kimmage?

Been arguing with mates about this for ages, never thought of asking here

Some friends of mine have recently moved to the Rafters Road, which is apparently postally in Drimnagh. Their relatives who have lived on Mourne Road for years all insist that it is, indeed, Drimnagh. The problem I have though is this: Once you take a photo anywhere from Herberton Road (which is practically Dolphin's Barn) to Rafters Road where they live, Apple's GPS will tag the photo as "Crumlin Town". And if you type "Crumlin" into Google Maps, it will draw a gigantic circle around the entire locality with the edges of that circle bordering Lansdowne Valley to the West, Kildare and Clogher Roads to the south, the canal all the way from Goldenbridge to Donore Avenue to the north and east. And ridiculously, right in the middle of this "Crumlin" circle is labelled "Drimnagh"

If on the other hand you type Drimnagh into the map, it won't circle an entire area at all, but merely drop a pin on the southwest corner of Brickfield Park. This would tend to corroborate my friends' insistence that their house is in fact definitely Drimnagh rather than Crumlin as Apple's GPS claims.

On the other hand, Wikipedia states that Crumlin Children's Hospital is in fact entirely within the boundary of Drimnagh. So all of this begs the question, where exactly is Crumlin?

I've hitherto taken a very simplistic approach to this and assumed that essentially, everything North of Crumlin Road up as far as the canal is Drimnagh, and everything south of that road is Crumlin. However, locals also insist that once you get to the Bangor Circle, Crumlin becomes Kimmage. This would seem to suggest that Drimnagh is a very big area, while Crumlin is comparatively tiny - which doesn't seem right given that Crumlin is regularly discussed as an actual area in and of itself rather than just a tiny add-on to Drimnagh. Also, Crumlin Shopping Centre is situation inside the triangle formed by Brickfield Drive, Crumlin Road and Herberton / Keeper Roads - despite the fact that according to my previous beliefs, this would be entirely Drimnagh and the shopping centre should therefore be named accordingly.

There are a lot of other discrepancies which have thrown this into confusion. I'm no stranger to the ambiguity of Dublin suburbs' boundaries, being myself from to which the postman will happily deliver letters marked Dun Laoghaire, Sandycove, Glasthule or Glenegeary, and which despite being beside Sandycove Dart Station comes up as Dun Laoghaire on Maps and is apparently "officially" postally Glenegeary... You get the idea. One of my neighbours takes the view that "The line between Sandycove and Glasthule is 'an idea'"... Go figure.
But the difference here is that there's a bit of cash riding on who was right about Crumlin and Drimnagh when it was recently debated, so I'm intensely interested in finding out if a definitive answer exists

Anyone have any insights here? Is it, like my area, just another of those areas of Dublin which lacks any clearly defined divisions between the different suburbs? Or is it another case of technologies such as Google Maps and Apple GPS being lazy and not actually looking at a proper map?

Attached are two Google Maps screenshots, one of a search for "Drimnagh" and another for "Crumlin". In the Crumlin photo if you look closely, the area Google regards as Crumlin is shaded in pink - while it shades nothing at all for a similar search of "Drimnagh".

And as if to make this even more ridiculous, the section of the canal they have used for the Street View preview is the exact same photo in both searches.