There's no point in using LineageOS after they dropped PrivacyGuard instead of expanding it. You start going down this road and suddenly you'll have a phone that doesn't pass SafetyNet anymore. You have to use 3rd-party applications and probably a ROM made by a random internet user not affiliated with LineageOS because they drop support for devices all the time. The phone manufacturers bribe ROM developers to do that or they just move on quickly.
MicroG is another really unstable experience. Google bought KaiOS and will buy the next KaiOS too. They moved and continue moving features to their proprietary castle. There's just no way you can win this fight against Google.
Long term the only solution is by some miracle a FOSS phone gets enough popularity for developers to want to make apps for it. I doubt it. My solution is unfortunately using two separates phones. Android and a FOSS one.
Privacy Guard) I was the one who purposely removed it. I spent days ( if not weeks ) trying to get it working properly ( read, it never worked properly and causes many issues we still have tickets for ) futhermore Google basically rewrote the full stack once again, while introducing the, now publicly available in 12, permission hub that somehow gave a better view of permissions and easy access to remove them. We know it removed some more granular ops, but it wasn't worth the effort.
SafetyNet) Nothing can legally pass it unless Google certifies it, we can't do much, only Google can enforce it to be used only for security related reasons
Bribing) I wish I got a single cent from any of the OEM I worked on, name it, Motorola, Asus, Huawei, OnePlus, Xiaomi.
Not once they threatened us to stop working on their devices, and at the same time didn't help at all ( the only outsider is Asus that is willingly to help )
We simply can't continue supporting every device that enters the door, we don't have any real way to improve it, everyone is doing it voluntarily with no expectation, and so do we as project directors.
I don't think anyone is especially happy about the LineageOS shortcomings you point out, but that's why people are working on supporting the mainstream Linux stack on existing hardware.
The LineageOS folks have a very difficult job to do, they must keep up with developments in AOSP while supporting dozens of existing hardware models, each with its own "exciting" quirks. Is it really any wonder that some hardware gets dropped from official support? Usually that just means bugs have turned up which would make LineageOS not fully usable on the hardware, and they don't have the volunteer manpower to address them.
Complaining about SafetyNet and microG is even less understandable, as these will always amount to unsupported hacks and we don't really need them for a usable device. Just get your apps from F-Droid, and you won't have to care about either.
I had not noticed that Lineage dropped PrivacyGuard. Damn, there really is no choice these days.
Lineage is also so frigging annoying how they just drop old phones. They won't even provide the last good build or previous builds. Really bad thinking over there in general I guess.
They do provide source for all devices, which you can just compile yourself. PrivacyGuard was dropped in order to provide compatibility with a loosely-equivalent solution that's included in AOSP, hence in most custom ROMs. Unfortunately, this also means that the supported feature set has regressed, and getting back to parity will take some effort.
MicroG is another really unstable experience. Google bought KaiOS and will buy the next KaiOS too. They moved and continue moving features to their proprietary castle. There's just no way you can win this fight against Google.
Long term the only solution is by some miracle a FOSS phone gets enough popularity for developers to want to make apps for it. I doubt it. My solution is unfortunately using two separates phones. Android and a FOSS one.