I second this. If Checkboxes and Checklists are different, and we choose to use a Checkbox (by the cumbersome new Insert method), why would the program designers think that hitting Return/Enter would mean we want to convert it to a Checklist.
I miss the old functionality, and request that if I enter a Checkbox, then hitting Return/Enter should actually start a new line with a new Checkbox.
In my daily use, and in both Templates and many current notes, I use a Checkbox to indicate an unanswered or uncompleted item. When completed I typically check the box and enter text at the end of