Popular traditions, are they really traditions?

[mitalit]

I put this topic in the Euskadi thread, but my question can be extended to the rest of Spain, Europe or the world.
According to a documentary that I saw some time ago, most of the Basque traditions (rowing, basket tip, euskal dantzak, sokatira, harrijasotzaile...) are inventions or in some cases reinterpretations of traditions with a very little diffusion made for tourists between the 19th and 20th century.
How many of the traditions we take for granted are actually traditions?

[Arūnas]

The first Russian nested doll set was carved in 1890 at the Children's Education Workshop by Vasily Zvyozdochkin and designed by Sergey Malyutin, who was a folk crafts painter in the Abramtsevo estate of Savva Mamontov, a Russian industrialist and patron of arts.[4][5]
The inspiration for matryoshka dolls is not clear. It is believed that Zvyozdochkin and Malyutin were inspired by eastern Asian culture, for example, the Honshu doll, named after the main island of Japan, however, the Honshu figures cannot be placed one inside another.[7] Sources differ in descriptions of the doll, describing it as either a round, hollow daruma doll, portraying a bald old Buddhist monk,[8] or a Seven Lucky Gods nesting doll.[4][5][9]
[B]Savva Mamontov's wife presented the dolls at the Exposition Universelle in Paris in 1900, where the toy earned a bronze medal. Soon after, matryoshka dolls were being made in several places in Russia and shipped around the world.

https://en.wikipedia.org/wiki/Matryoshka_doll