Short answer, Yes. TJ Watt is now the most dominant Watt in the NFL. Even Pro Football Focus agrees with that statement. They say he has now surpassed his brother as the game's most dominant Watt in the NFL. TJ Watt has been on an absolute tear in the NFL for the past 3 seasons. One can argue TJ Watt was the Defensive Player of the Year in the NFL for two seasons, but the Associated Press has decided to vote for another player each of the past 2 years. This season was Watt's year. Clearly, the AP has something against TJ for whatever reason. So again for the second year in a row, he was robbed of the Defensive Player of the Year Award.
In the past 2 seasons, TJ Watt has passed JJ for Sacks. In 2018 JJ Watt had 16 sacks and TJ Watt had 13. TJ has surpassed double-digit sacks in the past 3 seasons whereas JJ has only done it once. Granted overall JJ has had more sacks than his younger brother overall in the NFL with 20.5 sacks in multiple seasons. In each of those seasons, JJ won the Defensive Player of the Year Award (2014 and 2012).
Note this is an article about whether TJ has surpassed JJ for being the best Watt in the NFL right now. All of the statistics show TJ has passed his brother in the past 2 seasons except 1 category which was in 2020 (JJ had 6 higher assists).
See below for the statistics by year.
TJ Watt in 2019: 55 combined tackles, 35 solo tackles, 20 assists, 14 tfl, and 14.5 sacks.
JJ Watt in 2019: 24 combined tackles, 15 solo tackles, 9 assists, 4 tfl, and 4 sacks.
TJ Watt in 2020: 53 combined tackles, 43 solo tackles, 10 assists, 23 tfl, and 15 sacks.
JJ Watt in 2020: 52 combined tackles, 36 solo tackles, 16 assists, 14 tfl, and 5 sacks.
Clearly, TJ Watt has surpassed his brother JJ by becoming the most dominant Watt in the NFL. That is not a slight against JJ Watt because the one thing JJ has hanging over TJ is his Defensive Player of the Year Awards and that absolutely drives TJ Watt nuts.
TJ has tons of football left in him to get a couple of Defensive Player of the Year Awards, but I think he will need to surpass 20 sacks or at least match his brother with 20.5 sacks in a single season to get it. The Associated Press is a sham so in order for TJ to overcome their bias that will be the number he would need for them to vote him the Defensive Player of the Year in a single season.
Overall TJ can make as big of an impact in the game of football as his older brother JJ has, but he will need to stay in tip-top shape to do it and avoid what has plagued JJ throughout his career (injuries). I think the Steelers can manage TJ to keep him upright for most of his career barring any freak accidents. TJ is the best Watt in the NFL as we stand right now.