Prior to vSphere Lifecycle Manager (vLCM), the creation of an ESXi Image Profile was done separately using the vSphere Image Builder service. If you needed to download a specific ESXi Image Profile (ISO or ZIP) for importing into another environment or to simply create a bootable installer, it was intuitive to download the image within the vSphere UI.
With vLCM, both the ESXi Image and Configuration has been combined and it is now managed at the vSphere Cluster level. A couple of weeks ago, I needed to download a specific ESXi ISO from vLCM and it actually took me a bit of time to figure out where to perform this operation.
I recently came across a VMTN post where the user had the same challenge and realized I was not the only one who could not find the functionality in the vSphere UI.