Guidelines were changed for laypeople a while back because it turned out continuous chest compressions moved enough air and was more impactful in the first few minutes.
The reasoning I heard was that more people are comfortable giving chest compressions than rescue breaths, and we wanted to encourage people to help even if they weren't comfortable with rescue breaths
> Available evidence strongly support the superiority of bystander compression-only CPR. Reasons for the best efficacy of chest compression-only CPR include a better willingness to start CPR by bystanders, the low quality of mouth-to-mouth ventilation and a detrimental effect of too long interruptions of chest compressions during ventilation.
People don't want to make out with a stranger, they don't do it very well, and pausing chest compressions detracts from it.
