It looks like gamers are moving on from the PS4 at least with PS Plus freebies, and Sony is taking the hint.

Sony wants the PS5 to beat the PS4 in every way possible--sales, profits, services, accessories, etc. So any time there's an opportunity to sunset Gen8 features, content, or delivery, Sony might take it. Something like that is now happening with PS Plus freebies.
SIE today announced that PS4 games will no longer be a "key benefit" of the PS Plus Monthly Games and Game Catalog. Starting January 1, 2026, PS4 games are no longer guaranteed as monthly content for PS Plus subscribers, and Sony will offer free PS5 games instead.
This affects both the Monthly Games, which are the free games you get every month, and the Game Catalog, which is a huge treasure trove of back catalog games accessible as part of the PS Plus Extra and Premium plans.
It's unclear as to what extent this will affect the Game Catalog, but Sony notes that PS4 games will "still be available to play until it leaves the catalog as part of our monthly refresh."
Sony says that it may occasionally still offer PS4 games, or games that can be played on both PS4 and PS5 (which is a huge majority of games).
Check below for the update from Sony:
Update on PS4 Games for PlayStation Plus
As many of our players are currently playing on PS5 and have shifted toward redeeming and accessing PS5 titles from the Monthly Games and Game Catalog benefit, PlayStation Plus is also evolving with this trend and will focus on offering PS5 titles through the Monthly Games and Game Catalog benefit starting January 2026.
As we shift to PS5, PS4 games will no longer be a key benefit and will only be occasionally offered for PlayStation Plus Monthly Games and Game Catalog starting January 2026. We may still provide titles that can be playable on both PS4 and PS5 consoles after this date.
Please note, this won't affect the PS4 Monthly Games that you have already redeemed from PlayStation Plus. You'll continue to have access to games you've already redeemed as long as you remain a member.
For Game Catalog, PS4 games will still be available to play until it leaves the catalog as part of our monthly refresh.
We'll continue to evolve the experience of PlayStation Plus and optimize the benefits you receive, including exclusive discounts, online multiplayer access, online game save storage and more.
As we shift our focus to PS5, we look forward to adding new PS5 titles monthly for you to enjoy.