When will PlayStation 4 support be stopped?

[Absurdity]

I wouldn't at all count the time of 1.0, on account of 1.0 wasn't ever available on PS3 despite the promise it would be. Never happened.

That's also the reason why they developed ARR for the PS3 in the first place, which they never should have. But they had promised that XIV would be on the PS3 all the way back in 1.0.

By the time ARR released the PS4 was already out, the PS3 was already 8 years old and it's hardware was severely limiting for the game.

The PS4 has 8GB of shared RAM/VRAM when the average gaming PC today has 16 GB and will likely be 32GB by the end of the decade. The PS4 GPU may still render the game decently but the entry level CPU and small pool of shared RAM would definitely be it's limiting factor when it has since ShB.

This will happen even faster if the current trend of unoptimized games continues.
Monster Hunter Wilds eats almost 8GB or more of memory on it's own, 16GB is barely enough to run the game, operating system, peripheral software and a browser at the same time.