First couple shuttle launches had ejection seats, but were taken out prior to operational use.
The way that stupid shuttle was designed, there would never had been a practical way to escape
the shuttle, unless they went with a "pod" to get them out, which would have weighted too much.
The capsule concept, in use from the 50's, is a more practical way of escaping, but, NASA (and by
the way of a proxy, the congress), went with that stupid shuttle, then didn't launch it the way it was
intended (piggyback on a giant plane). They went with those stupid boosters, problematic at best.
NASA, congress, and of course the CONTRACTORS, wanted the shuttle because they sold it as
a "flying truck". So, instead of furthering our exploration of space, we just flew up and down in low
orbit, then, they came up with the space station concept to give the shuttle something to do.
It's been a great big money spending party. Put space exploration into private hands, which will
find a profitable way to do it, and space exploration will, to coin a phrase, take off.