That is suspicious.
The four-digit year IMO was typed in by someone who "wasn't there." Obama's registration number could be correct but whoever put it on the COLB had zero experience with the way things were until 1990s. (Yes, there were exceptions as systems where modified/developed after hardware capacity increased and 2000 approached.)
The two-digit year was the standard owing to 80-column punch cards, second and third generation computers. I worked on a RCA301 for example that had 10,000 bytes of memory. We just could not afford the two extra bytes -- and there was just on will or money to expand dates as the hardware capacity grew -- thus the Y2K panic.
So Obama's COLB may have the correct information but IMO it's not an authentic Hawaiian government document if it has that four-digit year in the registration number.
That is true, we didn’t have to start using four digits on most everything until 2000.
I saw a COLB from a guy born in 1930 that had 1930 in the number. I think it was posted here today because someone has another theory about it. To test that theory we need to see someone elses COLB born around 1961. But I saw the 1930 one on the internet. I think it is the same COLB
You yourself mention Y2K. Obviously, between the long form created in 1961 and the short form issued in 2007, Hawaii modernized their systems.