Can I change or delete an App Store review I wrote?
Yes, that is possible. Apple does not make it easy, but own reviews can be overlooked, adjusted and also deleted. This is also useful if e.g. the support could help with a temporary problem and solve it.
Reviews in the Mac App Store
Go to the Mac App Store, click on your account in the lower left corner and then click "View Information" in the header bar. In the "Manage" section, click the "Manage" button under "Reviews and Ratings". To delete a review, click the "Remove" button to the right of the desired entry.
To change text or the rating, click on the program icon and the App Store page of the desired app will open. Click on "Write a Review" to view your old review and change it, including the rating stars.
Reviews in the iOS App Store
If you want to change a rating for an iPhone or iPad app, go to the App Store on your iPhone and iPad and click on the top right button (your user icon), then on your account name and finally on "Ratings and Reviews". To remove an entry, simply swipe it to the left and tap the red "Remove" button.
To change a review or star rating, open the app regularly in the App Store and tap "Write a Review" again. The old content will then appear and you can customize it.