If Biden said "I would bring the DOW to 30k", you wouldn't expect him to first bring it to zero, or to arbitrarily start wherever it left off with the last president.
Perhaps it's interpretation but I read that as meaning the number starts at zero. Your example says "I would bring the DOW to 30k" which is different from what Biden said. He didn't say I will bring the vaccine to 100m he said I will get 100m people vaccinated in 100 days. While I can see how that could be interpreted the way you claim I also can and do read it the other way.
Either way I think at a minimum there should be attribution as 16.5m is a significant amount of people already vaccinated that the graph appears to give him credit for.
https://www.webmd.com/vaccines/covid-19-vaccine/news/2021012...