The match against Theo gave them hope and made them realize they were lacking compared to the Japanese. There were many analyses of the game tomorrow and generally, most of them were in support of the Japanese. It wasn't because Supreme Alliance wasn't good but because the Japanese were just too overwhelming.
Aside from You Sixin, Hoshino was also a player with world class skills. They weren't just members of the Japanese; they were also representatives chosen by the committee to participate in international competitions.
Moreover, the Japanese weren't just strong in their skills, they also had a solid fanbase. Each and every one of them could easily become a hot topic – and that wasn't just limited to their own country. For instance, Lin Chentao had once mentioned that Hoshino was his idol. To be respected and worshipped by a professional esports player showed a lot of his influence.