From my observations of the Potterverse, that society seems to be quite dated, looking at the attire and architecture in the magical world relative to the muggle world. An exception to this is the Ministry for Magic, however even that could be argued to be somewhat reminiscient of the 1940s or 50s with the fashions and and architecture also.
We can also extrapolate that, not just in England, but at least some other parts of the magical world still observe relatively dated technologies and fashions, as demonstrated by the Durmstrang ship and the (albeit flying) horse and cart from Beauxbatons. So, in some respects, the Potterverse society seems to be quite dated.
Yet, in other areas it seems that the magic society has is more advanced compared to what would ordinarily be expected of a society exhibiting such almost medieval fashions. For example, women's rights - the fact that there are female teaching staff, and quite senior ones at that, indicates some development beyond a medieval time. So some areas seem to have progressed.
So my question is this: has the Potterverse society actually stagnated in some aspects, for example architecture, technologies and fashion, as suggested by props and settings depicted in the novels and films? I am looking for authoritative sources to support or contradict this notion.