From Google:
Starting June 1, 2021, all new photos and videos backed up in High quality will count toward the free 15 GB of storage that comes with your Google Account or any additional storage you may have purchased, the same way other Google services like Google Drive and Gmail already do.
All photos and videos you back up in High quality before June 1, 2021 are exempt from this change and will not count toward your Google Account storage. This includes all of your existing content uploaded in High quality.
This was such a real life changing feature being removed.
Google is a for profit company… you look at youtube, where it is now vs a few years back… pushing you with more ads and subscriptions. They all play a long "bait and switch" game.