Why? You must (please, but they don't write that, they instruct you) expect changes to your Google Analytics account. Namely: Google is rolling out Google Analytics 4, the “next-generation analytics tool”, which will replace the standard version Universal Analytics that clients have been using until now.From July 1, 2023, no new data will be processed in the standard Universal Analytics properties. The previous “old” tool will simply no longer work.
Furthermore: "... To continue collecting data in Google Analytics 4 without interruption, you should set it up individually now. The sooner you do this, the more custom historical data will be collected in Google Analytics 4. ... Unless you have disabled the option, a Google Analytics 4 property will be configured for you soon. This step may already have been completed. Certain goals and target groups will be transferred from your UA configuration. However, this is not possible for some other elements, such as custom dimensions and metrics. If you set up Google Analytics 4 individually now, the most relevant data for specific conversions and target groups, as well as for other analyses that are most important to you, will be collected. ..." (emphasis added)
In other words: Google doesn't ask, Google just does. Google decides: “This will work for you, dear user!” Google sets it up, Google configures it, Google takes the data. And those who don't comply will be punished: they won't get any data. Take it or leave it.
