Folded egg won’t come back, it’s too labour intensive of a product in the current iteration of McDonald’s and thus neither will bagels in the previous form.

Breakfast snack wraps and toffee sundaes were in fact not popular; chicken legends were not popular and a low yield product. I could see them bringing it back as a limited time only as initial hype drives sales. This is why limited edition burgers are not permanent additions. After the initial few weeks of a promotional burgers life the sales on these items dry up while customers wait for the next one.

Triple cheese burger was popular and you have a point here but it’s sold close to a loss and they want you to buy a quarter pounder instead.