Looking at the Horford post (averaging 15/10/7), I think we should also appreciate how IT has done in these playoffs so far.
Averaging ~25 PPG, 6 APG, 4 RPG IN 36.6 Minutes/Game
Isaiah has done extremely well given the circumstances, and he's averaging around 25 PPG despite having only 20 points in Game 2 and 16 points Game 3.
He's doing it on 44% shooting, although the 3 point-shooting is really low (21%), but I don't expect it to be that low all throughout. He's shooting 82% from the FT line (lower than usual), but he's been 23/24 the last 2 games (Games 1-2 he understandably struggled a bit).
Overall, I think Isaiah Thomas is proving a lot of the doubters wrong so far, and while his defense is still not great, for the most part he's still doing his job, and has posted 2 games of 30+ points this series. Given the circumstances earlier in the series, IT has done well and is a big reason the team has won 3 straight to turn the series around.
Now hopefully the Celtics playoff run continues into May, and IT can continue to perform really well!