At the time I created it, I worked on Windows more often and I had a lot of trouble trying to find a Make build that works fine on Windows. The ones available for Windows are usually incompatible with the GNU version. So cross-platform support is one advantage of alternative tools.
Other than that, Task has a lot of features, so some use cases are not covered by Make.
That said, I'm not a Make hater. If it works for you, that's absolutely fine. Many people has found value in Task, though.
Congratulations on you project, hope to have once a project as succesfull as yours.
I would like to clarify that I don't mean to bash Task, just tired of critiques saying that Make is bad because is old, and Just and Task are better only because they are new.
At the time I created it, I worked on Windows more often and I had a lot of trouble trying to find a Make build that works fine on Windows. The ones available for Windows are usually incompatible with the GNU version. So cross-platform support is one advantage of alternative tools.
Other than that, Task has a lot of features, so some use cases are not covered by Make.
That said, I'm not a Make hater. If it works for you, that's absolutely fine. Many people has found value in Task, though.