Fix of the issue is now available in InDesign’s latest November’17 update.
Please upgrade to the latest version InDesign CC 13.0.1 for the fix.
If you are unable to see the update, go to Creative Cloud application and click on the context menu on the top right and click on Check for App Updates.
InDesign TeamScott commented
I have the same result as everyone else - this has not been fixed. Any Button or Form object that has been anchored is not tagged in the exported PDF.
Fix is available in version 13.1 of InDesign.
Please update to the latest version available to you via Creative Cloud Desktop application.
Adobe InDesign teamScott commented
Thank you for working on this fix, but it still does not work. Any anchored form object (e.g., text field, check box) still is not being tagged.
When I export an Id file to a PDF, unanchored form objects are tagged, but anchored form objects are still not tagged. My Adobe Acrobat Pro DC is up to date.