Linked clones are a very useful feature because they are fast and save enormous amounts of disk space.
So I don't understand why it is not possible to create them anymore via the ESXi or vSphere UI (using ESXi 6.7).
I have found several unanswered forum posts on this:
Linked Clones Prevalence in vSphere
how to create linked clone VM on ESXI 6.5 server using vSphere 6.5/6.7 ?
It would be nice to get some feedback from the company on to why this feature disappeared, and if it is going to come back in a future version of ESXi.