Because you have not tried it. It’s actually one of the best solutions around and nothing to do with Frankenstein. Apple makes a great Arm chip with a nice laptop around, good screen etc. and there is a very dedicated team/community that works on Linux compatibility just for these devices. That makes them in many regards better supported than many other “regular” laptops you could install Linux on. Even if someone wouldn’t be interested in a MacBook and just wanted a Linux laptop, I would probably recommend them to pick up an Apple Silicon machine and put Fedora Asahi on it, it’s that good. Also, Apple fully supports installing other OSes in their hardware and boot mechanism design, they’re not doing anything especially hacky, this is a regular Linux installation running directly on the hardware.
I love macOS, because that’s what I’ve been using for the last 20 years. But now it’s 2023, and after trying this out this has won me over. I don’t even care about the privacy aspects too much, I would be fine with stock macOS in that regard (it’s far better than Windows at least), but using this is a joy so I have maybe booted into macOS like twice in the last 6 months. Hey you don’t have to use it of course, but don’t call it Frankenstein. If this is Frankenstein, then macOS is an abomination I couldn’t even describe with my vocabulary.
Anyway, if you’re really on your macOS train, even though it’s proprietary software and I personally try to avoid that, Little Snitch is just far better than LuLu in every aspect. I have used both extensively. That being said, I don’t think these firewalls are always that effective, especially if you try to use them to stop the system itself from spying from you. Ultimately they rely on the tools that the system is providing and if you ever even slip up for a second and have them toggled off in the wrong moment, that might be the moment that some system daemon decides to upload all the log data of the last 6 months that you have been trying so hard to hide from Apple in one fell swoop. Might not happen to you, but there’s no real guarantee. Or you update macOS and the new version has some kind of “bug” which causes your firewall solution to not be able to see 100% of the traffic (like already happened multiple times with macOS updates).
You should also make sure you’re only ever connecting to DNS servers that block all the Apple tracking domains. You cannot outright block all connections to Apple servers, because that would include things like their OCSP server for checking validity of app code signing certificates and then you cannot start any applications. That’s just how the game goes. You use macOS, you gotta make some connections to Apple servers. That would serve as a weaker second layer in case your firewall ever has an issue (chances are it will). DNS of course cannot interfere with connections made directly to IP addresses, and the system might always decide to do name resolution in another way, but it’s a good part of defense in depth.
And because you asked for a list, there are many blocklists around, look at the Apple part of https://github.com/nextdns/gafam/blob/21c1d3a7ea533f3fdad79b944ac43776749daa73/gafam.json and here https://github.com/nextdns/native-tracking-domains/blob/6ede2ce38ecf58c56f460f1f084bb320ac3989e0/domains/apple etc. There are some services that are not completely clear-cut whether they are really a privacy concern or not, you would have to look into the respective functionality and decide by yourself.
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