My Apple ID keeps sporadically locking despite various troubleshooting attempts

My Apple ID keeps locking since several years now. Sometimes it locks 3 to 4 times per year sometimes it locks even multiple times per day. There is no visible action that I personally do that triggers this. Since it has been suggested to enable 2FA, I have tried this, however, funny enough the Apple ID was locked again during my trial period, so I disabled 2FA again. Also my partner has an Apple ID that also does not use 2FA and that one has never been locked. Also, I am very certain that no one else knows my password. It has never been written down anywhere, it has never been stored anywhere, and it has most definitely not been shared with anyone for any reason.

Other things that I have tried are renaming my Apple ID, changing the password, removing all old devices, even remove current device devices and have the system re-add them after I have logged into them. I have changed country, I've changed payment information, address, anything that I could possibly think of related to my Apple ID. Nothing that I have done so far changes this behavior of the account sporadically locking out.

Since I I pretty much only use Apple devices, this issue is causing me a big headache, since once the ID is locked, all my devices are logged out. This means the watch, the Apple TV, all mobile devices and all computers. People that want to send me an iMessage during the time that my Apple ID is locked, are unable to do so. This means if I don't immediately notice that my device has been locked, I am also missing out on messages.

When I particularly don't like about this, is the fact that every time I have to log back into the Apple TV, I have to ask everyone in the room to step out for a moment so they don't see the password that I enter. Especially if I want to host the movie night with friends that's utterly ridiculous.

I have spoken to Apple on a few occasions and so far I've been told there is no way to see why exactly my Apple ID keeps locking. As an IT engineer, I'm not really convinced that's the truth. There are always logfiles. I'm just not sure how to get to the person that can actually look inside them and help. Also, the emails that I am being sent about my ID being locked, do not contain any reason. I'm totally left in the dark as a customer.

Has anyone else experienced something like this and has been able to find a solution to this? I would be really grateful for any assistance in this matter.

[Re-Titled by Moderator]