For years we had guys like Boozer, Brand, and Sheldon and they allowed us to spread the court and shoot threes because they could single handedly battle for boards and get us second chances.
Yes, but if you examine the years 1998-2006 when one of the above was there, Duke made the final four in only three of those years.
That's a little better than recently, but it's not the only reason why they haven't done that well lately.

Also, people do forget that the '88-'94 run was also an anomaly, with matchups or plays that favored Duke in the regional finals.

In '88 they came up against an incredibly stupid coaching job by John Chaney, who let Mark Macon shoot for 6 for 27 when both Ramon
Rivas and Tim Perry (NBA player) could score under the basket. In '89, they beat a Georgetown team with Dikembe and Alonzo that couldn't
throw the ball in the ocean; in '90, they got in on Laettner's first miracle shot, and in '92 on his second. So basically, assuming that in '86
'91 and '94 there was no doubt about making the final four, they actually should have gone maybe four or five times, but not seven.
So, over time, the breaks have evened out a bit.