Yes, you may choose to not use Terraform Cloud at any point. Your configuration is in your VCS system and if you reconfigure the backend
then Terraform will automatically migrate your state out of Terraform Cloud. Note that you will lose all the additional functionality that TFC provides: remote runs, VCS connections, state management, etc. If in the future you choose to use TFC again, you can once again modify your backend configuration to "remote" and Terraform will migrate your existing state into TFC.
If you leave, please provide us feedback at firstname.lastname@example.org
so we can make a better product for you.