The Athletic reported the DW trade demand on Jan. 28, 2021. According to the report, his demand for a trade (which came five months after signing a four-year extension) was because he was disgruntled over the fact he had not been properly consulted before the team hired new GM Nick Casserio.
https://theathletic.com/news/deshaun-watson-trade-texans/WvPmavyoA708/
The team said they had no interest in trading him, so he signaled his intention to sit out the 2021 season.
The first lawsuit against DW (ie: the first time he was publicly accused of sexual misconduct) was filed March 16, 2021.