I corresponded with my doctor via email and am following their advice on vaccination. Before saying more I want to point out that the advice I followed was specific to my personal circumstances and everyone should be getting medical advice (edit - MEDICAL ADVICE FROM A MEDICAL DOCTOR) for their own personal circumstances. I received my second booster dose in early December, same time as the flu vaccine. I have no underlying health concerns, am physically fit, and would be in the age range of 40-49. I got the booster because I have a few family members that are immunocompromised, and dealt with a family member that had their cancer diagnosis and treatment delayed when the hospitals did not have the capacity because of COVID patients. I didn't want to have it weighing on my conscience if one of those family members ended up sick with COVID knowing I didn't do everything I can control. I have two kids in elementary/primary school, and my wife and I discussed vaccinations with them and they chose to get vaccinated, but we decided against getting them booster doses.
Waning after 3 months is for immunocompromised individuals, pulled from that article:
“Pfizer BioNTech COVID-19 booster doses significantly improve protection against omicron, although while that protection stays high for immunocompetent patients, it seems to wane for immunocompromised patients after 3 months against emergency room visits, and even for hospitalization,”
After 3 doses in immunocompetent individuals, effectiveness against omicron-related hospitalization was 83% at less than 3 months and stayed high at 79% at 3 months or longer.
Against emergency department visits that did not result in hospitalization, protection was high and stayed high for immunocompetent individuals (approximately 78%), but remained at suboptimal levels in immunocompromised individuals (approximately 50%).