That is a problem with how the governments treat layoffs vs quitting. In attempting to make companies and individuals responsible for more unemployment benefits, they made a number of large cracks for people to fall through.
It a problem with corporations too. They’re not bound by the laws of physics to leave you high and dry. Anyway, the point of the GP question was if it was necessary to give notice after you started your new job.
Given that companies are almost always choosing to leave people high and dry, the rational response is to not let yourself get into that situation by not giving your employer advanced notice
On top of all this, you also lose unemployment benefits if you quit your job and the new one has rescinded their offer. As far as the states are concerned, you voluntarily quit your previous job, and never started a new one