The space shuttle was an awesome feat of engineering, but in practical terms, it cost a lot for every launch, so it really didn't deliver well on the most important piece of what reusability is supposed to get you.

The tiles themselves were apparently a big source of the problems on the shuttle too. If they can figure out reusable tiles with starship, with quick turnaround and low-cost for maintenance, that'd be a huge engineering accomplishment.

They've gotta consistently re-enter it first though.