Being open source doesn't prevent the software being made with features one may dislike. It does mean you can actually investigate what data is being collected and decide if it shouldn't be doing that.
When I have installed Windows I've clicked "no" many questions asking if I was X feature on, and I could only hope it was respecting my wishes. It was probably still collecting data it didn't even ask me if I could turn off.
Being open source doesn't prevent the software being made with features one may dislike. It does mean you can actually investigate what data is being collected and decide if it shouldn't be doing that.
When I have installed Windows I've clicked "no" many questions asking if I was X feature on, and I could only hope it was respecting my wishes. It was probably still collecting data it didn't even ask me if I could turn off.