The question https://mathoverflow.net/q/286985/41291 obviously belongs elsewhere. Most probably the proper place is physics.SE, but in any case not here on meta, not on math.SE, and not stats.SE (it could be accepted there but still there are better choices).

So when proposing to close it as off-topic I do not have correct choice. I realize that the off-topic list cannot be too long, but still I believe at least physics.SE could be there since cases as this must be not that exceptional.

**In few minutes**

Although this was not on the **Related** list, browsing through recent questions I discovered https://meta.mathoverflow.net/q/3428/41291; practically this one is a duplicate of it, but let me still leave mine here as it contains another obvious example.

**In few more minutes**

Following further links, also found https://meta.mathoverflow.net/q/2214/41291; a proposal to add academia.SE has been declined, and an answer there explains that the general policy is to severely restrict default migrations since mutual contention of sites is involved. I think I will still leave my question open for consideration.