I just did some research (not exhaustive by any means) and it looks like they graduated 4 seniors last year and brought in 5 freshmen which included a 5-star and 3 four star players (rivals ranking). Did I miss something? If not I don't see any comparison between the two teams.
They had 2 4 star top 50 players redshirting last year. Nigel Williams-Goss from Washington, who was just named a 1st team all-American. Also Johnathan Williams, a Haith recruit from Mizzou.
In addition to the 2 starters named above, 4th year transfer from Cal, Jordan Matthews, also a 4 star is a starter, as well as returning 5th year 7-1 senior Przemek Karnowski.
The 5th starter is soph Josh Perkins, another 4 star #67 who started all 36 games last year.
The top freshman recruit is 6-11 Zack Collins, a Rivals 5 star #21. The 5 starters only have 5 years D1 experience at Gonzaga, but 12 years of D1 including those years at Cal, Washington and Mizzou.
They also have a few other role players with experience including Bryan Alberts, who started 10 games for the Zags last year.
As is Few's recruiting philosophy, he supplements D1 transfers with freshmen. With that experience and star power, it's no wonder they've been rated #1 this year and are a top 15 team most years.