The article studies properties of a nationalist group, which is in extreme minority, especially after 2010s, and doesn’t make claims that ‘most Russians are nationalists’.
You have to lurk really hard to find a nationalist there unless you count people love Dostoyevsky into this group. There are also a lot of glass ceilings in place for ethnical Russians, and distribution in elite universities, politics, and business don’t represent the country average, which suggests there’s an intentional ’reverse racism’ in place towards majority. Moreover, the word ‘Russian’ is banned in media and is replaced by ‘citizen of Russia’.
As an example: https://academic.oup.com/edinburgh-scholarship-online/book/2...