I dont want to start a fight or anything like that, I have to decide between these 2 and cant figure out which is the best and why, mostly because if you ask on X they just start swearing to each other without giving any real explanation, can anyone help a person who want to embrace privacy and anonimity?
Well, if you want to activate an esim on any other Android rom, you need to use Google services and have an internet connection. DivestOS is the first rom to implement an open source version of eUICC, which is used for activation, called OpeneUICC. It also does not need an internet connection, so nobody knows that the esim is installed on your device. That is, until you actually use it, of course. This is in line with DivestOS actively trying to "deblob" (remove binary, closed source parts of) Android.
The second part, about why sim is not very private, well it has a unique identifier and the technology was specifically designed to pinpoint your location, as this helps keep a good connection.
Also, why did my comment get downvoted?
GOS also have esim implementation without google
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Ah yea, that's true. But at least you can remove it after activation it seems. https://github.com/GrapheneOS/os-issue-tracker/issues/159#issuecomment-1292329307
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SIM cards contain authentication keys for the cellular network so it knows who to bill and which cells to send a paging signal over to ring a call. The use of SIM cards does not pinpoint your location, and SIM cards have absolutely nothing to do with keeping a good connection (pSIM or eSIM). The network and handset are constantly re-evaluating signal strength across various bands and modes and the network tells the handset to switch to what works while moving about the network. The SIM just auths the user account. It is ostensibly a key to your service, nothing more.
All the network band/mode hunting will continue with or without a SIM card, the phone would just be limited to emergency calls in that state.
I don't think you understood half of what I wrote correctly. Feel free to skip the next paragraph if you already know about triangulation in the context of cell towers.
Your phone, when connected to a cellular network, can be tracked by cellular towers. Take a single tower to which you are connected. The tower has a multitude of devices which are connected to it. Since latency is a large issue due to distance, communication is less trivial. To prevent waiting for packets from a device for too long, the cell tower will divide a certain time into sectors. In each of these sectors, one device is supposed to send it's packet. To hit this time window however, the device has to send it's packet in advance, as to cancel out the latency of the transmission. By how much is determined by the distance between the cell tower and the device. This system requires knowledge of distance. This distance has to be close enough to the real distance, to cancel out latency and maximize the time a device can send data. With obstacles that may reflect the waves, the preciseness of the distance determined is correlated to the stability of the connection. Given that a lot of people can be using a cell tower at once, there are towers which are segmented. These work slightly differently than non segmented ones, in that they have multiple antenna sending and receiving signals in different directions. A segment of a tower with 6 segments would then be responsible for all devices which are in the area of 60 degrees from the tower. The distance together with the general direction already gives us a pretty accurate depiction of the user's location. However, since most towers are neither segmented, nor would a say 6 segmented one give as accurate of a reading if the device is 3 miles away (that would be a possible curve of pi(≈3) miles which the device could be on, given a perfectly flat ground), let's make this even more interesting. With a simple, rough time stamp, we can find out the location of a device up to an accuracy of a single point. Add a second cell tower, make the device connect to the towers one at a time and you have the exact position of the device. Well, pretty close to exact at least.
With that said, the reason why a sim card is the issue in this constellation is the unique identifier. If a network of cell towers can determine where you are located and the imsi is tied to your identity, then your location is tied to your identity. And if you think, even for a second, that mobile internet providers would not take advantage of this, think again. A very popular example of this are malls wanting to know where their customers came from.
Now, if you have a device with GrapheneOS (DivestOS too I think, don't know) for example, then you will have the ability to entirely switch off the cellular antenna of your phone (which one should likely do if they don't have a sim anyways). This is supported by hardware due to airplane mode, where the airplane requires least interference.
Now that I have explained in more detail, do you understand better why a sim card is a privacy concern?