I think everyone understands that the playoffs are different than the regular season. There are going to be a few players on every team that played and helped during the regular season that don't in the playoffs. Refs call the games differently. Match ups get more focus as teams play up to 7 times in a row.
I think a team's big rotation is a factor in the playoffs. Just one of many. In most series, the Celtics will have the best/deepest guard rotation and wing rotation, but not the best or deepest big rotation. In the regular season, we had games where Jrue Holiday was the primary defender on Giannis and Randle for stretches. We won't always need a third big, it depends on how much 1-big vs. 2-big we are able to play. But I think there will be times when we need something from a third legitimate big, not just relying on Jrue Holiday to cover a PF.
Our "third" big is going to be a combination of Kornet, Tillman, and Queta. All of these guys did fine enough in the regular season but the playoffs are different. I am not sure how these guys will fare in the playoffs. It is the weakest link on a really good team. I still feel that the Celtics can get through the east and get to the finals. The finals are going to be tough, but the Celtics will likely be favored, if they get there.
No one matches up well with Giannis and Randle is out for the rest of the year. Which other PF’s are going to be a problem for the C’s in terms of mismatches?
You are correct that PHI does not have a true PF either. MIA, NYK, ORL are all teams that play will low pace and get their share of offensive rebounds. The Knicks in fact lead the league in Orebs, even though they didn't have Randle for a chunk. MIL scares me the most, but we'll see what condition Giannis is in. CLE is another team that plays slow and has length (they just don't have wings).
We should be able to beat any of these teams based on overall talent. With Randle out, Giannis potentially limited, and Embiid potentially not holding up, it all favors the Celtics, at least in the East. No team is perfect. There are more teams with more size in the West but fortunately, we only have to beat one of those teams.
What I see is that because the Celtics have less size (talented size anyway) than most teams, we have stretches were we give up offensive rebounds, and we rely more on the 3. More 3 point shots by definition means more variability in makes, less free throws (Celtics were 26th in FTA in the regular season, 1st in 3PA). You might make 45% one game, 35% the next, maybe even as low as 30% for a game or a half. Bigger teams will get more 2nd chance points and more FTA.
That doesn't mean bigger is always better. In a 7 game series, you hope the 3P% averages out. We have more weapons than any other team. But teams are going to be able to key in on their size advantage over the course of a series. There are ways that the Celtics can counter that. In general, in games that we hold about even on offensive rebounds, we tend to win (or so is my perception). I think we will hold even or better on turnovers (we should at least). We should be able to hit more 3s most games.