https://www.gamespot.com/articles/free-ps3-and-ps-vita-games-not-included-in-ps-plus/1100-6457063/

From March 8, 2019, Sony will no longer offer PlayStation 3 and PlayStation Vita titles for free as part of a PlayStation Plus subscription. In a PS Plus update on the PlayStation Blog, the platform holder said it "will focus on PS4 titles" instead. The company has since confirmed to GameSpot that it will not be replacing the lower number of free games with more PS Plus games, meaning the total number of games given away each month with PS Plus from March next year will be two, down from six right now.

"This won't affect any games you've already downloaded, or will download, prior to March 8, 2019," it continued. "Those games will still be part of your PS Plus games library as long as you remain a member." It emphasized that game saves and other benefits will not be changed.