Seems GWR have updated their menus in First Class and now only provide sandwiches for "journeys of three hours or more" - so that is hardly any of their trains then.
Images show photos of the GWR first class menu.
The image provided refers to 'services of 3 hours or more in duration', not 'journeys of three hours or more'. The distinction may be important.
To me, this suggests that sandwiches won't be loaded for (eg) Paddington-Bristol/Cardiff, but they will for Paddington-Plymouth/Penzance. However, the wording doesn't preclude sandwiches being offered for
journeys of less than 3 hours (eg Paddington-Pewsey) on Plymouth/Cornwall trains.
We'll see what happens in practice. Sandwiches have never been abundant on GWR, so in theory this could be an upgrade for long distance West of England trains, if the sarnies are now loaded consistently. Though the service hours of 11.00-15.00 are limited.
Wine was a once-a-week thing on GWR, wasn't it? Now every weekday evening.