We have seen cases where _gen tasks take a long time to be dispatched to a host. One example observed in a patch build had noPassthrough_gen waiting for 37 minutes before it got run. This in turn delayed the noPassthrough task because it is the responsibility of noPassthrough_gen to activate noPassthrough.

Prior to SERVER-57003 and SERVER-64731, each _gen task would directly run the generate.tasks commands. Quoting from Evergreen's Task Priority documentation: "Tasks that generate tasks are prioritized over tasks that do not." This means the _gen tasks are no longer prioritized as highly as they once were. While removing the _gen tasks isn't practical because we still want engineers to have the option to run a subset of all tasks, we can change the task definitions so _gen tasks are prioritized higher again.