I maintain enough competence to know when it looks like it could be critical so I can call for help, but realistically that's happening anyway as soon as someone gets unstable as I haven't resuscitated someone in years.
I haven't looked at a real patient's ECG in probably 7 years now. If you were the patient, would you even want me to? I'd rather just do the smart and safe thing, call for help.
No subspecialist (or even specialist) can maintain competence in all areas of medicine, it's hard enough keeping up my general radiology skills. It's a good thing none of us practice in silos by definition.
You have basically agreed with me. I made no statements about subspecialisation or attempt to reconcile the breadth of medical knowledge that is required as you progress through medical training into consultant status with that original knowledge, or implied that we're expected to be able to definitively diagnose and manage a patient with a ECG that implies an imminent threat to life.
Frankly I think that everyone should still be able to recognise a STEMI - it's pretty characteristic; the more severe or subtle AV blocks definitely take some familiarity; but the bedrock principle of ACLS is calling for help, and medicine is certainly a team sport