There have been L2s at various points in time for apprenticeships and things like that. They keep changing it so not sure if those folks are officially L2s anymore or even what the program is called.
Also there are L1 staff in data centers IIRC.
It’s not that confusing, for most roles you just start counting at 3.
There are also plenty of L2s on eng job ladders outside of SWE. The levels are kinda sorta roughly equivalent by pay across different roles, hence levels 1 and 2 don't exist in SWE because their pay is below the lowest any SWE would be making.
There was a transition period (think it was 1-2y) where nobody would be promoted to 7.5 anymore. People who were already 7.5 had the duration of the transition to try to get promoted to 8. If they were still 7.5 at the end of the period they were converted back to 7.
I am pretty sure the period in which you were at Google was after the transition started
Also there are L1 staff in data centers IIRC.
It’s not that confusing, for most roles you just start counting at 3.