Agreed. I'll go a step further, if we get a fully healthy Tatum/White + a partially healthy Brown & Jrue season + '24 Horford/KP they will hit the Pelton OVER. Basically, the combo of Tatum and White are the key to winning many games.With regard to the starting 4, yes they will be fine. The Thinking Basketball guy did a two-part series on the Top Teams from the "Pace and Space Era" (I've not gotten to their rankings yet; the two shows are almost 3 hours long) but they mentioned that the 3 Js and White were 56-15 when they played together, or a 61-win pace. Assuming decent health from those 4, they will be way over Pelton's 52 wins.
This isn't to say White is better than Brown or Holiday but his style of play is more conducive to winning regular season games. Under the intensity of the playoffs, Brown's D & his brute strength are more important. The same probably applies to Jrue in the playoffs.
Last season's Celtics bludgeoned the NBA, we don't need that level of performance to win a LOB (but it would be nice)