This is like a reverse-dupe situation. The people who actually made the boots (NPS, a co-op in the UK) never owned the brand [0]. Then in 2013, the brand was acquired by a PE company [1] who did what PE companies do and got cheap, nasty, versions of the boot made in East Asia.

So the "dupe" non-branded version is actually the original, and much, much better quality than the branded official version of the product.

[0]https://en.wikipedia.org/wiki/Solovair [1]https://en.wikipedia.org/wiki/Dr._Martens