I got the same issue on Xcode 26.
1k targets in spm
apx 10-20 Libraries in Packages
We used local libraries of SPM for modularity on Xcode.
Tried dynamic / static.
On Xcode 16.* no crash by SWBBuildService.
That happened when we have apx 990 targets by SPM.
When my project had 840 targets by SPM, it doesn’t have crash.
UPD: I made some research.
When your graph have 1003 targets SPM, it works, no crashes
