Vmware ESXi -- reclaim space you need to run unmap command from Vmware server.

Kindly run refer below.

esxcli storage vmfs unmap -l (label name)
or
esxcli storage vmfs unmap -u (UUID)

Refer the VMware Knowledge base.
https://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=2057513

or https://youtu.be/5pWI0K0iJA8



esxcli storage vmfs unmap -l MyDatastore

or

esxcli storage vmfs unmap -u 509a9f1f-4ffb6678-f1db-001ec9ab780e