From the development roadmap it seems that the plan is to eventually replace projectile with project.el and taskrunner. It is worth noting that taskrunner hasn’t been updated in almost two years, although the package might just be feature complete.
Even so, there doesn’t seem to be a good interface between taskrunner and completing-read (only ivy , helm , and a WIP one for ido that isn’t ready to be used per the readme), which hampers the use of this package with :completion selectrum. Unless I’m missing something the only solution to this is to write a consult-taskrunner package, which might not be that hard because one could just copy ivy-taskrunner and change things around.
Also it seems that taskrunner depends on projectile so I’m not sure how the eventual replacement is supposed to work.