New Parasite website ranking No 1 for every keyword on google

Been seeing Researchgate website been used as parasite and it's ranking no 1 on google for most keywords, my question is how are they getting access to the website and publish content on it, I tried signing up but seems only Institutional email can have access

The people posting their parasite on this website, what do you think is their strategy? Are they buying those researchgate accounts