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In september 2020, Tails has been started more than 906 004 times (30 200 boots a day on average). source

Kind of disturbing an operating system that is designed to be super secure is spying on it's use.

They just count how often a security report is fetched and an update check is performed. Both are done once when tails is booting. So I would not call this spying (both calls are made through tor, so IP leaking).