I have a lot of tasks in Reminders (macOS, Catalina) with subtasks. In Reminders they are grouped under parent task.
In GoodTask (on macOS) they showed as separate tasks, without any grouping.
Is this correct?
Hi @Vsubb, thanks for the feedback.
Yes, that's correct. Subtasks info in Reminders app is not opened from Apple to use for 3rd party devs.
I'll keep an eye on it and will check when Apple opens it.
Thanks!
Has there been any update or movement on this? Really hoping some compatibility between GoodTask and the native Reminders subtasks and tags will come into play. Really love GoodTask, but have a lot of shared lists with the wife who only uses Reminders. The lack of compatibility there is causing me to start to consider dropping GoodTask.
Unfortunately Apple didn't make any changes since then. You may give them a feedback to make them move. 
Hello! Checking to see if this is still the case? I am in the middle of migrating to Reminders and plant to use Goodtask in the future. I have several recurring tasks in reminders with subtasks. I noticed that they are separated in Goodtask as well.
If this is still not possible, I assume i instead just create the subtasks in Goodtask?
Yes, still you can’t get subtask related data from Reminders app. 
For simple subtasks, using text based subtasks in GoodTask will be fine and useful. If you need to organize it with more detail, adding separate list or using tags would be a way to go. Thanks!