Common misconception.
1) The Jazz's defense is designed for their wings to be more aggressive because they have safety net at the hoop in Gobert. This yields lower quality opponent shot selection as seen in fewer 3 pt attempts & layups.
2) Also Gobert is among the top iso defenders against all but the very elite guards (harden, curry, dame)
https://www.forbes.com/sites/bendowsett/2020/06/29/rudy-goberts-improved-perimeter-defense-is-an-major-tool-for-the-utah-jazz/.

Yes, this style is different than other schemes of "perimeter defense" but the Jazz have largely shown that it is highly effective over the last several years.

Also, you don't really need more than an 8-9 player depth. The Jazz had 7 last year before a STEEP dropoff and only 6 during the playoffs with Bojan out. This year they have at least 8 before relying on Niang, et al. They don't need much more depth.