"right to choose to continue group health benefits provided by their group health plan for limited periods of time under certain circumstances such as voluntary or involuntary job loss, reduction in the hours worked, transition between jobs, death, divorce, and other life events. Qualified individuals may be required to pay the entire premium for coverage up to 102% of the cost to the plan."

Yeah, no, that's not the same thing at all. As a Canadian I have health coverage I can, y'know, live with regardless of whether I'm employed or not. And buying coverage in the US (with a pre-existing condition) was absolutely not worth it (even considering the wage gap) when I entertained a few offers in the early oughts.

Staying here means I have substantially better freedom of movement and negotiating power. In the US the "freedom" to not have healthcare just seems to mean that everyone has the "freedom" to pay more - and often for less.

Looks like it might be hard to ensure coverage for very long if the reason for losing your job was the employer going bankrupt.

Are there other systems aside from Cobra that pick up where Cobra doesn’t? E.g for bankruptcy , companies smaller than 20 employees?

Yes, you are still legally allowed to pay many thousands of dollars for healthcare if you are laid off.