"Tracking" is a nebulous term. If a company records your visit in their logs, is that tracking? If they increment a counter every time someone visits a page, is that tracking? If a user logs in under Incognito Mode and the site records their new last login IP and timestamp, is that tracking? These questions would have sounded facetious years ago, but now nearly every form of user tracking has come under scrutiny.
The common confusion is that Incognito mode isn't equivalent to using Tor or a VPN. For 99% of cases, that doesn't really matter. Explaining the distinction to the average user is a challenge, though.
> Wouldn't the world be far better if a phone alerted me to an app scanning my local area network or contacts? Or if I got warnings when it took such actions?
Modern phone OSes will ask for permission if an app wants to access your local network, your contacts, or your photos. That's not the concern here, though.