The problem isn't about the big corporations themselves but about the fact that the network itself is always listening and the systems the big corporations build tend to incentivize making as many metadata-leaking connections as possible, either in the name of advertising to you or in the name of Keeping You Safe™: https://en.wikipedia.org/wiki/Five_Eyes
Transparent WWW caching is one example of a pro-privacy setup that used to be possible and is no longer feasible due to pervasive TLS. I used to have this kind of setup in the late 2000s when I had a restrictive Comcast data cap. I had a FreeBSD gateway machine and had PF tied in to Squid so every HTTP request got cached on my edge and didn't hit the WAN at all if I reloaded the page or sent the link to a roommate. It's still technically possible if one can trust their own CA on every machine on their network, but in the age of unlimited data who would bother?
Other example: the Mac I'm typing this on phones home every app I open in the name of “““protecting””” me from malware. Everyone found this out the hard way in November 2020 and the only result was to encrypt the OCSP check in later versions. Later versions also exempt Apple-signed binaries from filters like Little Snitch so it's now even harder to block. Sending those requests at all effectively gives interested parties the ability to run a “Hey Siri, make a list of every American who has used Tor Browser” type of analysis if they wanted to: https://lapcatsoftware.com/articles/ocsp-privacy.html