Perhaps you don't remember what happened to Apollo 1.

According to TFA, what happens when you close the visor is that the oxygen starts flowing into your suit. The suit is open-loop, not closed-loop, so the oxygen goes straight into the atmosphere of the shuttle cabin. Quite a lot of oxygen, actually. So much so that it becomes a fire hazard, like what happened to Apollo 1, where you risk a single slightly marginal connection sparking and creating a firestorm in a shuttle that would have otherwise landed.

The problem is that the shuttle was designed so that nobody would need to wear a spacesuit except to do a spacewalk and then mildly corrected so that you have a slightly reduced chance of death in an accident.

Spaceplanes don't have to use a ceramic tile, just the space shuttle, the way they designed it required either ceramic tiles or reusable ablative coverings (which was optional in the design for a while in case the ceramic tiles turned out to be impossible, but hasn't been mentioned since)

One aspect of the X-33 that never got tested (which bugs me) is the reusable refractory metallic heat shield. See, the denser the craft, the gentler the reentry. If the shuttle was less dense, perhaps by having the orbiter integrate at least some of the external tank's capacity, it might have been possible to make one with a less delicate shield.

The main reason why the ablative non-metallic heat shields on capsules are essentially foolproof is that you re-enter on a piece of shielding that's been kept covered the whole flight. You could likely make a capsule with a reinforced-carbon-carbon reusable shield if it weren't likely to shatter when it hits the ground.

Not even that.

Consider the A-10, with the titanium bathtub around the pilot so you can shoot all you want, but he's still sound.

Now, consider strengthening the crew cabin so that in the event of a structural breakup, they have a fighting chance of bailing out. No capsule. No separation. Just a little more plating or Titanium instead of Aluminum in the right spots. Remember, both the Columbia's and the Challenger's crew cabin held together for quite a long time.

The real flaw, but only painfully evident in retrospect, was not making something like the Saturn-Shuttle, like the X-20 atop a Saturn II, or even a reusable first stage for the existing stack. Likely taking a Saturn IB, II, or V stack and making it reusable bottom-to-top would have worked out far better.

The problem was barreling forwards with blinders on, not going back and checking assumptions. It wouldn't have been such an edgy design had it been more like the initial DC-3 concept or had they re-evaluated some of the early designs that were rejected for not being fully reusable or making sure that abnormal things like O-ring wear and tank debris weren't more carefully controlled.

By "Configure the suit for full protection" that means put on the gloves and push down the visor. All of the controls are designed for a unsuited crewmember, the visor gets in the way and requires you to be on your oxygen system. And the oxygen system is pure O2 so you can't keep it running because there will be too much O2 and not enough N2 in the atmosphere of the shuttle.

So, no, there's no possibility for a dead-man's switch in the current design. But it's clearly something necessary in a future design. Even airline passengers are protected against depressurization and airliners are fairly safe.

Consider the SR-71 pilot referenced in the report. He didn't eject, his plane broke up mid-flight, yet he survived. Granted, different thermal environment, but same degree of overpressure.

So, to me, there were things that could have been different that might have resulted in a chance for at least some of the crew to have landed alive.

That really doesn't do the report justice. You couldn't add magic restraints, better spacesuits, self-activating parachutes, etc. to the shuttle and expect for crewmembers to survive the accident, but there are a lot of more subtle design points to be made.

e.g. the example of the person who survived a SR-71 structural breakup, at even greater overpressure on the suit but with a more favorable thermal environment and while properly suited up.

The big and fairly underappreciated lesson of both shuttle accidents is that the crew cabin survived for quite a while longer then the vehicle at large. To me, thus suggests there are benefits to be had in figuring out which large structural segments of a crewed spacecraft... even a capsule that can survive uncontrolled re-entry... are going to survive the longest in a catastrophic failure and see if they can last long enough for the crew to bail out. Sure you've just lost the vehicle, but at least you might recover some of the crew.

Insisting that the only way up and down is in a ballistic capsule is throwing the baby out with the bathwater. Something like the Soyuz is fine for now, but there are plenty of ways to make a spaceplane that are not quite as flawed as the shuttle.