What do other users see when you delete WhatsApp - briefly?
When you delete WhatsApp, other users will no longer be able to send messages to your number or view your profile picture and status updates. However, they can still see the group chats you were part of, but your name in those groups will appear as "This person changed their phone number".
What do other users see when you delete WhatsApp - in detail?
When you delete WhatsApp, the experience for other users depends on several factors. If you simply uninstall the app from your device without deleting your account, other users will still be able to see your profile information and any messages or media you have sent in the past. Your contacts list remains intact, and you will continue to receive messages, which will be stored until you reinstall WhatsApp on the same phone number.
However, if you decide to delete your WhatsApp account permanently, the changes are more substantial. After deleting your account, other users will no longer see your profile picture or any information associated with it. Your messages and media will still be visible in their chat history, but they will not be able to start a new conversation with you unless you reactivate your account. Additionally, group chats you were part of will display your name as "This person changed their number."
In summary, the visibility of your WhatsApp presence to other users hinges on whether you merely uninstall the app or take the step to delete your account entirely.