To-Do Integration with Multiple Services

To-Do under iOS can sync with a personal account or a work/school account. Unlike other iOS apps--Outlook, Excel, Word, PowerPoint, OneDrive, all of which sync to multiple accounts--it is impossible to connect To-Do with both one's work and one's personal task lists. And iOS Outlook does not include a task module, unlike its Windows ancestor. For as long as To-Do has been public, MSFT has said that syncing to multiple accounts is on the way. Why is multiple account integration, which was fundamental to the other apps named above and necessary for most people with busy lives, not a higher priority for the To-Do team? Is there some workaround I haven't found?