You need to toggle off the "Show Home Controls" option or wait until you have at least 6 or 8 things to control so it can fill the space. You can add the old home control icon back if you wish. It's a stupid design.
iOS 14 started out really well with the first beta. Loads of little design issues like the above (and the gaps between the icons and dock etc.) which we all assumed would get fixed. Then they released 8 betas and fixed none of them