Wait till March 3rd, and then we’ll see.
No nominee of either party has been 5th in New Hampshire and 4th in Iowa. Going back to 1952, I don’s see a nominee of either party who didn’t come in at least 1st or 2nd in either Iowa or New Hampshire. e.g. Reagan came in 2nd to Bush in 1980 in Iowa but won New Hampshire and there were 6 candidates so full fields are not that unusual.
You can add the rank of the two primaries to get score and sense of how far Biden has fallen, e.g. in Iowa Biden finished 4th, and in New Hampshire 5th so Biden gets a 9.
No nominee of either party has ever had a rank of over 5 or 6. e.g. In Iowa, 1992 with an Iowa Dem Senator running, and sex scandals breaking Bill Clinton finished 3rd or 4th if you count uncommitted, but finished 2nd in New Hampshire so give him a score of 5/6 .
McCain came in a close 4th in Iowa in 2008 and won New Hampshire so a score of 5, these are the highest I have found and note they each came in either 1st or 2nd in one of the two.
Biden might defy history because the country has higher % “people of color” in other states but I don’t think so.