Even a defibrillator is only useful for certain rhythms, and the automatic type you usually see in public is more limited than a manual unit like a Zoll you'd find on a crash cart or on the EMS buggy. Now I am ACLS certified, but I do not work in critical care and have to date never run a code on a living person. You really want someone trained in giving good chest compressions, someone to assess rhythm and shock if warranted, someone to ventilate, and someone to push drugs. In a situation without trained pros and equipment, CPR and AED would be the first line of treatment until emergency services arrives.
Unfortunately, when a person is lying in the floor, unconscious, and in cardiac arrest, all of those necessary items you listed are not available.
I am ACLS certified also ( have let my certification expire due to old age and no longer working).
I was shocked to find out how few rural fire departments ( especially volunteers) and rescue squads actually carry defibrillators back in my day.
I hope that has changed. Without a defibrillator, a massive heart attack victim has 8-12 minutes max to restore circulation or suffer permanent brain damage, as you well know.
Terrible situation that could often times be mitigated with proper training and equipment.
Praying for the family and all ML fans today. God give them Grace. The next few days, weeks, months, and sometimes years are going to be very difficult for them .