For me the sad part about the story is that someone who clearly knows what they are doing wasn’t able to find a job that would have permitted him to continue working on the project and that there were insufficient sponsors from companies.
Database backup tools are used primarily in enterprise context. (In)Ability to donate is not a function of personal spending preferences
A fair amount of people work here at orgs on here would absolutely be able to swing couple of hundred bucks per month in sponsorship or licensing or donations for a critical tool in their infra toolkit without lot of effort.
Particularly so, with the rising frequency of AI deleted my prod posts.
The source is still available. Maintaining your own copy and/or paying someone to do it is an option.
While you're at it, look at all the projects you depend on that you would similarly be sad about losing, and set up those donations today.