I don't think my resources are wasted. But what do I know...
Generally, it is not nice to open duplicate topics in different forums at the same time and have multiple people spend time on doing troubleshooting without knowing the details/answers from the duplicate topic. Whether you care is up to you, of course. I've only pointed out the netiquette.
If you don't care about netiquette, oh well.
Your logic is completely laughable. You're saying that because there is no known issue and that "Steam is smart enough" this is a non-issue.
However, I'm telling you, Belf, that is definitely a problem for me. And I'm simply looking for help where I can find it.
The only resource here is time. And everyone on this board has plenty of it, I assure you (that's why we have time to play games like PoE).
That's a fallacy. For the QA person in this tech support forum, time is limited. The more you follow the guides in the sticky topics, the more helpful that may be.
I've only told you what is known about PoE and Steam achievements in general. They have unlocked fine since 2016 for many people at Steam. Nowhere do I rule out that there may be issues in corner-cases, and that's why at Steam some questions have been raised about your console usage, for example, and about using ancient savegames.
You may need to be patient and provide some details, such as a savegame file uploaded to a public place, so if a developer with limited time gets to read this topic, some good input is there. Else the developer will need to spend extra time on querying you.
Know that flaming me doesn't lead to anything.