In essence, it is about the increased transfer of user data to Facebook (and other companies belonging to the group). If you refuse your consent, you will no longer be able to use the most popular of all chat apps from that point on.
Europe has an advantage
Data has been collected for a long time
So far, so good, but comparatively little is gained. The fact is that WhatsApp has been collecting various usage data for a long time, following the pattern: Who communicates with whom – and where, how often, for how long and via which devices? In addition, there are unique device identifiers and, last but not least, all stored phone numbers (albeit without the associated names) in order to be able to regularly check whether a contact stored in the smartphone is also a WhatsApp user or not.
There have always been doubts about the company’s assertions that the data will not be passed on to Facebook. In the future, there is at least the certainty that data will be passed on; regardless of how this data is (may) then used.