nowhere it was mentioned that it was only a one-year subscription.
Yes, it was. From bottom of Object Desktop page [
Link]
After that year has passed, all the apps included in Object Desktop will continue to work without limitations for ever, but you will no longer have access to updates & betas, and if you wish to reinstall the apps you purchased, it is adviced to keep a backup of the installers & serial number(s), because the installers will no loger be available for download from your account page [Link] without a subscription