I started with the 1st Aid Merit Badge in the early 1970s. A lot of what I learned is still quite valuable. Sure, it can be updated, but most of it won't kill anyone faster than just standing by waiting for help to arrive.
I take Red Cross 1st Aid and CPR w/AED courses biyearly and have done so through 3 renewal cycles. The CPR w/AED is pretty good but the 1st Aid pretty minimal. The courses are designed for those who MUST take them as part of work requirements, so many participants view it as an unnecessary waste of their time. That rubs off on the instructors and makes it all less useful.
As a diver, I take the DAN courses, which are SCUBA-oriented, but students and instructors are much more engaged.
So-called Tactical Combat Medicine courses come in many flavors. And yes, many add some "tacticool" stuff to spice up an otherwise bland topic. I thought it useful to hear combat medic instructors talk about the strengths and weaknesses of different tourniquets, chest seals, compression bandages, etc., then slapping them on others to see how easily I could do so in a rush. And how easily I could do so on myself when shot in my dominant arm or a leg.
Drills included countdowns to loss of consciousness in getting a tourniquet on myself. Some brands suck and others are better. Same with compression bandages. It seems that when the USG puts out a supply bid request, plenty of companies are suddenly formed to make products that are lowest bid but minimally acceptable. While some of that gear might be "what the combat medics carry", it's not the stuff you want to carry or have applied to you, it turns out. A lot of people chuck out what Uncle Sam gives them and buy good stuff to save those they care about. Maybe civilian EMTs do that too?
I've worked in the medical industry for 25+ years trying to make things that actually work well and don't hurt people. It's easy to do one or the other, but hard to do both. Only recently have ERs, hospitals, MDs had to reveal statistics on success and failure - it's always been "internal" reviews hidden from view due to legal liability. But insurance reimbursement has pushed safety and efficacy of devices and procedures into more review, even if not open public view. Sometimes for the better, sometimes not.
A lot of ER, Trauma and Burns medicine is "that's the way we do it here" - the MDs come and go and the nurses & EMTs stay on. And "that's the way we do it here" sometimes isn't the best way, or even one of the better ways, to do it. Because a lot of those folks are focused on doing it, not evaluating themselves compared to everyone else.
So I'm a fan of meta-analysis in medicine. It sometimes tells us what might seem to be a great idea really is better, isn't really better, or is actually worse. If that's telling others who know their jobs what to do, sorry about that.
Some might say that sounds condescending (that's a big word that means talking down to people) but I don't agree.