Well, I cannot speak for the company, so I will skip the first two questions : ) However, I wil gladly address technical questions.
Thank you for passing the FSF agent test.
Now on a more serious note, the a) above was sort of technical question as well - is there an option for one to en masse convert the backups to some (albeit less capable) open format in case of an abrupt need for exodus? Thinking thousands of VMs, so something automated.
As for open-source components - there are a few items that are open-source, you can find them here:
https://github.com/veeam
Our largest open-source project is blksnap:
https://github.com/veeam/blksnap
Oh thanks for this! I actually did not know that e.g. the kernel module actually WAS open source.
From my point of view, it is great that current users of Veeam have a way to migrate between hypervisors. At the same time, once they have done so to a free solution, I would suggest to them to start asking for more free (i.e. at liberty to inspect, modify, redistribute) software.
As I have been roasting the same blend here less than a fortnight ago in respect to Proxmox themselves - and as you can tell they are nice people NOT moderating such posts, I felt it to be appropriate to point out that
Proxmox own's backup solution actually falls in that category for anyone coming across this thread post-migration.
(Note: I do not actually care for pricing difference between the products in that aspect, that's everyone's commercial decision to make.)
PS I actually found it hilarious that since "Veeam community forum does not allow non-commercial domains to be used for registration", you used this avenue, but no hard feelings.