For many, the "cost" of Tanzu is now baked into the broader VMware foundation bundles. Broadcom has collapsed the product catalog into four primary tiers, with Tanzu embedded as follows:
Tanzu on-prem requires vSphere 7/8 with Enterprise Plus licensing. If you don't already own it, add before you even install Tanzu. vmware tanzu licensing cost
That’s a for many customers.