Tkachuk has a few more points than Dahlin, a defenceman, so how does that mean he could end up being better? You take a 7 game ppg statistic, and extrapolate that over an entire season to make a point that he's a talented point producer like his brother, who has always put up better numbers at every level of hockey.
I literally provided an analysis of the underlying performance numbers for both Matthew and Brady a few pages back.
Matthew Tkachuk
Season 1: 0.64 pts/g, 0.17 G/g - projection over 82 games of 52.48 pts and 14.21 g
Season 2: 0.72 pts/g, 0.35 G/g - projection over 82 games of 59.9 pts and 28.94 g
Brady Tkachuk
Season to date: 0.63 pts/g, 0.31 G/g - projection over 82 games of 51.66 pts and 25.42 g
Performance post trade deadline: 0.71 pts/g, 0.41 G/g - projection over 82 games of 58.22 pts and 33.62 g
In his first season Brady is performing at almost the same rate in pts/g and in G/g he is performing similar to Matthew in his second season. Some had been concerned how Brady would perform without Stone, the post trade deadline performance offers that analysis. As we can see since the trade deadline Brady has been producing at a pts/g rate comparable to Matthew in year 2 and his G/g is actually meaningfully higher than Matthew in year 2.
The data suggest that your opinion is wrong. Matthew may have produced more points at different levels but so far the data suggests that Brady is producing at a very similar rate to Matthew. Given that Matthew has done a tremendous job offensively this season and Brady has similar numbers to Matthew's earlier seasons, it suggests that Brady might be on a similar development rate.
As for the 7 game ppg statistic you missed the point. That was demonstrating that as the season has progressed his underlying numbers are improving quite rapidly. Producing at a point per game and 0.72 G/g even over that small sample size is impressive considering he is on the worst team in the league with very few talented players and he doesn't have Stone with him.
It seems pretty clear that you have a negative view of Brady and that you aren't open to having your opinion changed.