Why won't my Mac let me drag and drop?
Go to settings and check if everything is correct there. Go to the Apple menu > System Settings > Trackpad (or Mouse). In the Trackpad settings, there is an option called 'Force Click and haptic feedback. ' This can sometimes mess up apps and features on your Mac, like drag and drop.
Why is drag and drop so hard on Mac?
A Mac's drag and drop function not working can be due to incorrect settings or an out-of-date operating system, software, or firmware. Mouse and trackpad preferences can also often confuse as there are several options users can select to customize how an item is selected and moved via Mac's mouse cursor.