Honestly I feel PD might have lost interest in Gr.4 in general. While it is still featured almost weekly in daily races, they even dropped it entirely in Manu from last year (to the point that Mazda's loaner was never updated from the Atenza Gr.4 to Mazda3 Gr.4).
Yep. Seems like once GR.4 was no longer an unbalanced mess, they just gave up on it. I can only assume the user numbers are what have driven this because why else would they not do anything else after adding entries for Genesis and Suzuki?
Also (and this is just a personal thing from me, gonna be abit long): There's the awkward question of why some manufacturers are even still in it when (Apart from not even being in contention for the World Series):
- Citroen has NO relevant vehicles suitable for either class and their single entry for both classes is based on a concept from 2008 (Hell, the GR.3 entry is 15 years old at this point). Are they even still in Motorsport at this point?
- Renault Sport is literally Alpine now (Their engine program in F1 this year is basically the last remnant of anything officially "Renault" left in Motorsport and its basically dead in 2026) and their entries for both classes are basically a One-Make silhouette and a Locally homologated version of a One-Make silhouette. We'll just ignore the GR.4 FF monster that terrorized GT Sport because frankly I like the Trophy car better sound and looks wise.
- Dodge has the Viper for both classes in much the same way Ferrari still has the Ferrari 458 (The GT3s are from the same time period even I believe). However, their fellow Stellantis Brand has a replacement for GR.3 coming in December that currently races basically everywhere and if they wanted to, there is technically a Gr.4 replacement to consider in the form of the 296 Challenge. Whereas that Viper hasn't raced in high level Motorsport since...2016? There is nothing to replace the GR.3 entry and Dodge's motorsport presence is currently...some nitrocross EV thing (which does sport a sick livery). Even the GR.4 getting a replacement is highly questionable because basically what is there to replace it?
- Alfa Romeo is similarly questionable as Dodge at this point with cars far outdated and just like Citroen, do they even have ANY motorsports involvement? Other then the brief tease of a potential Hypercar/GTP entry, there's been...nothing (as far as I'm aware anyway). Even that stubborn black & Gold entry in IMSA has been retired.
- Hyundai as a brand have been long replaced by Genesis which sports cars for both classes AND GR.1 (Though good luck controlling the hellish amounts of wheelspin).
- Apart from those trucks I see in Thailand Super Series, Mitsubishi might as well be dead as a Motorsports brand.
And speaking of Renault being replaced: Why no Alpine as a brand in the Manufacturers Cup? The Renault Group is pushing this brand so hard yet there is NO representation fictional or real to be found. There's a GT4 car so that's a slam dunk GR.4 entry, They could make a GR.3 car going off what they did for both Alfa Romeo and Volkswagen and then of course a perfect GR.1 addition (and competitive Toyota GR010 rival) in the form of the A424 for anything Nations Cup.
So many questions I have regarding all this yet sadly, there is part of me that wonders if the simplest answer is that the brands in question just don't care themselves.