Jimmy Graham signed for 4 years, $40M. Gronk signed for 6 years and $53M three years ago. Jason Witten signed for 5 years, $37M four years ago. Vernon Davis signed a very similar deal one year earlier.
Olsen deal seems right in line with who he is. He's one of the best TEs in the NFL. Not as dynamic as Graham or Gronk, but then again, he's not making as much as them either.