I am in the same situation, If you just want to delete your account, it seems accessing this url : https://www.facebook.com/help/delete_account does not trigger the consent message.

If you want to access Facebook and Instagram without accepting the ads, there are some weird ways I found that kind of works:

• For Instagram in a browser you can go to https://www.instagram.com/consent/?flow= this will go to a page that says “Sorry, this page isn’t available.” but you can then go to the homepage without triggering the consent message. (some actions like loading a story will though) Another way on mobile (tested on Firefox android) is to start from the browser and when the consent message shows up click on the 3 dots → “Open in an application” the app then open to a blank page and you can go back to home.

• For Facebook this tricks doesn’t seem to work, but other ways seems to, like using https://mbasic.facebook.com/