IND playoff points per game: 114
BOS playoff points per game: 108
IND playoff opponent PPG: 111
BOS playoff opponent PPG: 98
It's better to look at per-possession stats, because pace is such a factor.
https://www.nba.com/stats/teams/advanced?sort=PACE&dir=-1
Overall, we have been about 9.2 points per 100 possessions better than them so far.
Are you looking at the Net per 100 Possession (NRTG)? That is fair. They are scoring more but so are their opponents. That is clear no matter what set of numbers you consider. The net per 100 poss is a little elongated as compared the net per game as the pace for both teams is <100 (93 IND, 91 BOS).
When I check team stats per100 poss, IND is 121.7 pts/100-poss, BOS is 118.9 pts/100-poss. IND is scoring more per possession and has been playing at a higher pace also (more possessions per game). TS% is the same for both (60%) but they are better for EFG% (58.1% to 56.9%). I think the difference is TS% considers FTs, which BOS is taking and making more of to offset the more FGs they are making.
We are going to have to slow them down, both in terms of pace and in terms of shot making (eliminate easy buckets they create off of pushing the ball). That is no secret. And it will be harder to slow them down than it was to slow down either CLE or MIA (who were trying to slow us down). But it will also be easier to score on them. Again, this is all pretty obvious. Even Charles Barkley will probably recognize this.