They are doing it 10 years later, so probably computer simulations are going to simplify the job more for them than they did for SpaceX.

Also Bezos has more cash and less dependent on external funding or public opinion - if several of his rockets blow up in a row it won't stop him, and he can proceed quicker.

Also, New Shepard uses hydrolox. That is harder than Falcon's kerolox. Not to say New Shepard is more comples than Falcon 1 - they are very different vehicles hard to directly compare - but it's definitely not a toy.