It's not purely a case of vendor lock-in, but that shouldn't be downplayed too much. Virtualization is still very much applicable for the legacy applications which are still prevalent. New apps may run in containers, but it's not just a few big companies running ancient legacy software.

When you refer to smaller company and mention docker, or open source, it's only those that are tech startups, or close to the field with the skill to operate in this fashion. The majority of small and medium companies don't have the skills or resources to do this. Over time that changes, but it's completely unrealistic to think that they can get away quickly from VMware (even when their overworked IT person would like to.)