The Soy Community refers to those who soy post as a group. Individuals are known as soy posters.
Other names include: Soyjak posters, soy spammers, soyjak spammers, and often derogatorily and incorrectly, wojak spammers or "wojackers".
The soy community mainly gathers on the sites Soyjak.party, the SoyBooru, and the Soyjak Wiki, where you are right now. The /qa/ board of 4chan is also a hub for soy gatherings, and many Soy Duels can be seen and even participated in. The latter board is infamous for its intermittent banwaves against soyposters, though.