another russian's player win valorant major
The circuit for valorant and csgo are pretty different, so it just kinda depends on how important you think the masters are. Majors are basically the most prestigious tournaments in csgo, so the equivalent for valorant would be champions, but masters is also an international lan with top teams, so some people say masters are also comparable to majors.
In other esports, Major is a tournament which is directly funded by the game's devs. For example TI in DOTA and the Major in CSGO. However, Riot funds all the global tournaments like masters, champions in Valorant and MSI, Worlds in LOL. So, there isn't really a definition for Major here, just that Champions is the biggest tournament of the year with biggest prizepool, production and no of teams, that's why it's a major and masters is not.