could you enumerate them, please?

Oracle - don't use an Oracle database unless you hate money, yourself, or your company.

SAP - getting off of their ERP systems is an absolute nightmare and they know/exploit that fact.

Salesforce - CRM systems, in general, can lead to lock-in due to the sheer amount of data and customization they host. In recent years Salesforce has started to leverage this fact to grow revenue without adding value.

Unity - they're getting aggressive in trying to extract more money from their existing customers and I'm not referring to the recent license changes. Nightmare company that you should avoid working with on enterprise software at all costs.

Blackboard - within the education section their LMS is challenging to migrate off of and they will bend you over backwards because they know it.

ServiceNow - they've seemingly given up on making a better product and have invested all their efforts in extracting more money out of their current customers.

PagerDuty - whose sales rep who told me straight up that they didn't need to negotiate with us because it would be too difficult to switch away from their product.

For specific product lines IBM, Cisco, and VMware also do this but I don't think it would be fair to characterize that as their overriding business strategy like the above.

Thanks.

Personally I hate those "give me more free info" responses. Do your own homework.

Albert, I must assume this was targeted at my comment to ask for an enumeration of businesses enjoying the model espoused. "Do your own homework" is fine if the objective is clear; it wasnt (to me at least) and I wasnt sure where to start. Thank you to the OP for adding that list!