It is nesesary

Hello guys, do you have any suggestions about Loopback? Is it necessary to use a Loopback on my network? All of my routers directly point to my aggregate switch, including my WAN IP. Thank you for your suggestion.

Loopback in routers is in principle not needed ... but often it is needed but to solve some particular issue. So unless you run into some such issue, you don't need loopback(s).