Windows 8.1 drops extended support in 2023. Windows 7 already ended in 2020.
Despite this, 12% of windows users globally, and 6% of USA users, still use Windows 7. This is actually larger than the share who still use w8.1 (3% both USA and globally)
Why is continuing to use Windows past its support deadline dangerous? And if it is dangerous, why are there still SO MANY windows 7 users?
what privacy violating features does windows 8.1 have?
Data collection and personalized ads (mainly using your browsing/search data).
The real question is what privacy violating features doesn't modern Windows have? Given the vast number of 'User Experience' and 'Telemetry' and 'Reporting' services and scheduled tasks running all the time, and those are just the services that openly confess to sending data, we'll likely never know. Some of the most egregious issues are the services to do A/B psychological testing on you by changing around Windows elements, anything you type in Start Menu, anything you say in its vicinity when Cortana isn't pulverised to the ground, any time you log in without a super-special local-only account, masses of personalised info gets sent to Microsoft.
Edit: I do still have Win10 for playing a few games that won't work on Linux though. So shoutout to ShutUp10 for being a decent way to disable a large portion of the madnesses. https://www.oo-software.com/en/shutup10