But since the official Electoral College certification of his victory, Biden has taken several swipes at Donald Trump and his administration.
He has put his oar in on the congressional battle over Covid-19 relief money, vaccine rollout planning, and transition 'roadblocks' put up by some administration officials.
Dealing with the coronavirus and getting shots in arms will be the key early task for Biden as president and what he will be judged on.
He is now clearly communicating to the public that vaccine distribution is not going to plan - and who is to blame for it.
Yesterday he said: "As I long feared and warned the effort to distribute and administer the vaccine is not progressing as it should".
He added that at the current pace, "it's going to take years, not months, to vaccinate the American people".
Part of this is about giving himself leeway and managing expectations, essentially: It was bad to begin with, they are making it worse, don't expect miracles, it will take a long time.
But it is also a continuation of a strategy to present a contrast with Trump that Biden has benefited from over the past year.
There's the Biden straight talk, the highlighting of unwelcome information, a regularly stated concern for people affected, a methodical approach, and an attempt to take the issues seriously.
That compares to four years of Trump chaos, erratic decisions, focusing on personal grievances, the settling of scores, and fanciful fiction-spinning.
Trump continues to make the contrast easy for Biden because it goes well beyond political calculations and optics, to the reality of two very different characters.
It is relatively simple for Biden, at this stage, to fill the void Trump creates when he fails to take logical actions. The actual clean-up work once he goes will be harder.
Take the vaccine rollout. Biden has a goal of 100 million shots of the vaccine out within his first 100 days in office. He promises to send a bill to Congress covering expanded vaccinations and testing, use the Defence Production Act to increase vaccine production and protective equipment, and has added new members to his Covid-19 response team.
It is what would be expected of a political leader who wants to be considered competent and is trying to set up an administration of experienced, normally dedicated people.
The man still in charge has been spotted working on his golf swing in Florida while the one part of the US pandemic response that had appeared to be working, Operation Warp Speed, has turned into Operation Snail Mail.
Trump Administration officials had planned to have 20 million doses of the coronavirus vaccines distributed by the end of the year. However, the Centres for Disease Control said that about 11.4 million doses have been distributed but only 2.1 million people have received their first jab.
Trump responded to Biden's criticism by blaming states. Both the organisational failures and finger-pointing between the federal and state levels are familiar from earlier problems with testing, funding and protective equipment.
"It is up to the States to distribute the vaccines once brought to the designated areas by the Federal Government," Trump tweeted. "We have not only developed the vaccines, including putting up money to move the process along quickly, but gotten them to the states."
As the US lurches towards January 20, things could get worse. A case of the fast-spreading British virus variant has turned up in Colorado without known links to travel.
According to ABC News, 70 Americans test positive for coronavirus every 30 seconds.
One in 17 Americans - 19 million people - have tested positive. One in 1000 have died from the virus.
A conventionally half-competent response from Biden after his inauguration would look brilliant compared to the past year.
