It's possible that the increased traffic between Moscow and Beijing is due to the affordability of travel and accommodation in Russia. As a Chinese person who grew up in Guangzhou and visited Russia in 2016, I was surprised to find that the prices for food and accommodation were similar to those in Guangzhou, except for Chinese food which was more expensive. This could be a draw for Chinese tourists who are on a tighter budget and are interested in experiencing European culture and history without the higher costs associated with destinations like London and Paris.