Firstly I am really sorry that this has happened, and I understand your frustration. The reasons it has happened are as follows:
- The ROM includes the Sony Camera app and a settings panel called Xperia Parts. These have been in all the unofficial ROMs that I have built for liac, and they are in the first official release too. They are not present in the other two devices I support (z3c and suzuran), I guess because they are older devices.
- As the ROM maintainer, I was asked to remove these from the lilac ROM, for reasons listed below.
- Removing them is not straightforward, and I would have to spend quite a bit of my own time working out how to remove them. Experience suggests that it would be a long, error prone, and frustrating process In any case, I have no wish to spend my free time working out how to make the software worse, so I said that I would step down as ROM maintainer.
- Without a ROM maintainer to support it, the ROM cannot be official.
I was given the following reasons for removing them
There is 3 reasons why we ask you to remove Sony Camera:
- Consistency across all devices: we want each of our users to have
the same experience, doesn’t matter the device he is using /e/ onto
- We avoid to embed proprietary apps inside /e/ (the only exception on
that is about MagicEarth, and we got some warranty with the editor)
- Sony didn’t allow us to embed their camera app inside /e/
We know that proprietary camera apps are often working better than /e/ Camera (based on OpenCamera), but at the moment we have to deal with that. Users are still able to install Sony Camera by their own.
I am not convinced by reasons 2 and 3: this device is part of Sony’s Open Devices  program. The source for the Camera app is in github  and it appears to be licensed under the Apache License, Version 2.0 . So as far as I can see, it is Open Source and not proprietary, although it is vendor- and device-specific.
So it comes down the the first reason, that /e/ want all their devices to provide the same user experience. I don’t happen to agree with that approach - which is why I stepped down as maintainer - but it is /e/'s project so they make the rules: if we don’t like the rules, we don’t have to play
As I said, I plan to continue making unofficial builds for lilac - with the Sony Camera app included. I will investigate the possibility of providing OTA support, but I make no promises, and it certainly wont happen very soon.
(An interesting point is that several other official /e/ devices are part of Sony Open Devices. It would be interesting to know whether the official /e/ ROMs for those devices include the Sony Camera app )
Again, my apologies.