I have to tell you that you have no channel to delete some built-in applications on Mac and Podcast is one of them. If you want to perform the Podcast deletion for more disk space, I would like to recommend you an excellent toolset to free up the Mac hard drives -- iBoysoft DiskGeeker.
iBoysoft DiskGeeker is a wonderful disk management tool for Mac. It is a comprehensive disk utility for Mac users that can help access Windows volumes, clone a disk, repair a disk, clean junk files, and encrypt disks. It can enhance the protection of your data and improve your work efficiency.
You can utilize iBoysoft DiskGeeker to clean the junk files for more disk space instead of deleting Mac built-in apps.
Step 1: Free download and install iBoysoft DiskGeeker on your computer.
Step 1: Select a partition from the left panel.
Step 2: Click "Clean Drive" from the toolbar.
Step 3: Select the file(s) you want to delete and click "Delete All" to free up the space.